1321131420 has 72 divisors (see below), whose sum is σ = 4579926624. Its totient is φ = 301972608.

The previous prime is 1321131407. The next prime is 1321131437. The reversal of 1321131420 is 241311231.

1321131420 is a `hidden beast` number, since 1 + 3 + 211 + 31 + 420 = 666.

It is a super-2 number, since 2×1321131420² = 3490776457822432800, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 1321131393 and 1321131402.

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, 522999 + ... + 525518.

It is an arithmetic number, because the mean of its divisors is an integer number (63610092).

Almost surely, 2^1321131420 is an apocalyptic number.

1321131420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1321131420 is an abundant number, since it is smaller than the sum of its proper divisors (3258795204).

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

1321131420 is a wasteful number, since it uses less digits than its factorization.

1321131420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1048539 (or 1048534 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 1321131420 is about 36347.3715693446. The cubic root of 1321131420 is about 1097.2746361255.

Adding to 1321131420 its reverse (241311231), we get a palindrome (1562442651).

The spelling of 1321131420 in words is "one billion, three hundred twenty-one million, one hundred thirty-one thousand, four hundred twenty".