1021312440 has 96 divisors (see below), whose sum is σ = 3323239920. Its totient is φ = 272024064.

The previous prime is 1021312433. The next prime is 1021312471. The reversal of 1021312440 is 442131201.

1021312440 is a `hidden beast` number, since 1 + 0 + 213 + 12 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 532924 + ... + 534836.

Almost surely, 2^1021312440 is an apocalyptic number.

1021312440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021312440 is an abundant number, since it is smaller than the sum of its proper divisors (2301927480).

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

1021312440 is a wasteful number, since it uses less digits than its factorization.

1021312440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3413 (or 3406 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1021312440 is about 31957.9792853053. The cubic root of 1021312440 is about 1007.0542669711.

Adding to 1021312440 its reverse (442131201), we get a palindrome (1463443641).

The spelling of 1021312440 in words is "one billion, twenty-one million, three hundred twelve thousand, four hundred forty".