697731981 has 8 divisors (see below), whose sum is σ = 943412544. Its totient is φ = 458603040.

The previous prime is 697731971. The next prime is 697732019. The reversal of 697731981 is 189137796.

697731981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 697731981 - 2⁵ = 697731949 is a prime.

It is a super-2 number, since 2×697731981² = 973659834620368722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (697731941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1637656 + ... + 1638081.

It is an arithmetic number, because the mean of its divisors is an integer number (117926568).

Almost surely, 2^697731981 is an apocalyptic number.

It is an amenable number.

697731981 is a deficient number, since it is larger than the sum of its proper divisors (245680563).

697731981 is a wasteful number, since it uses less digits than its factorization.

697731981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3275811.

The product of its digits is 571536, while the sum is 51.

The square root of 697731981 is about 26414.6168058520. The cubic root of 697731981 is about 886.9440198505.

The spelling of 697731981 in words is "six hundred ninety-seven million, seven hundred thirty-one thousand, nine hundred eighty-one".