1331898981 has 64 divisors (see below), whose sum is σ = 2140508160. Its totient is φ = 720944640.

The previous prime is 1331898977. The next prime is 1331898989. The reversal of 1331898981 is 1898981331.

It is not a de Polignac number, because 1331898981 - 2² = 1331898977 is a prime.

It is a super-2 number, since 2×1331898981² = 3547909791177676722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331898989) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7975360 + ... + 7975526.

It is an arithmetic number, because the mean of its divisors is an integer number (33445440).

Almost surely, 2^1331898981 is an apocalyptic number.

It is an amenable number.

1331898981 is a deficient number, since it is larger than the sum of its proper divisors (808609179).

1331898981 is a wasteful number, since it uses less digits than its factorization.

1331898981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434.

The product of its digits is 373248, while the sum is 51.

The square root of 1331898981 is about 36495.1912037737. The cubic root of 1331898981 is about 1100.2475974325.

The spelling of 1331898981 in words is "one billion, three hundred thirty-one million, eight hundred ninety-eight thousand, nine hundred eighty-one".