1312213428 has 36 divisors (see below), whose sum is σ = 3324683908. Its totient is φ = 436389120.

The previous prime is 1312213423. The next prime is 1312213433. The reversal of 1312213428 is 8243122131.

1312213428 is a `hidden beast` number, since 1 + 312 + 2 + 1 + 342 + 8 = 666.

1312213428 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1312213423) and next prime (1312213433).

It can be written as a sum of positive squares in 2 ways, for example, as 837060624 + 475152804 = 28932^2 + 21798^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×1312213428² = 3443808161247022368, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1312213423) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 26503 + ... + 57678.

Almost surely, 2^1312213428 is an apocalyptic number.

1312213428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1312213428 is an abundant number, since it is smaller than the sum of its proper divisors (2012470480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1312213428 is a wasteful number, since it uses less digits than its factorization.

1312213428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84624 (or 84619 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 1312213428 is about 36224.4865802126. The cubic root of 1312213428 is about 1094.8000936124.

Adding to 1312213428 its reverse (8243122131), we get a palindrome (9555335559).

The spelling of 1312213428 in words is "one billion, three hundred twelve million, two hundred thirteen thousand, four hundred twenty-eight".