697918221 has 256 divisors, whose sum is σ = 1548288000. Its totient is φ = 304819200.

The previous prime is 697918219. The next prime is 697918229. The reversal of 697918221 is 122819796.

It is not a de Polignac number, because 697918221 - 2¹ = 697918219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (697918229) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 22513476 + ... + 22513506.

It is an arithmetic number, because the mean of its divisors is an integer number (6048000).

Almost surely, 2^697918221 is an apocalyptic number.

It is an amenable number.

697918221 is an abundant number, since it is smaller than the sum of its proper divisors (850369779).

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

697918221 is a wasteful number, since it uses less digits than its factorization.

697918221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102 (or 82 counting only the distinct ones).

The product of its digits is 108864, while the sum is 45.

The square root of 697918221 is about 26418.1418915108. The cubic root of 697918221 is about 887.0229277806.

It can be divided in two parts, 6979 and 18221, that added together give a triangular number (25200 = T₂₂₄).

The spelling of 697918221 in words is "six hundred ninety-seven million, nine hundred eighteen thousand, two hundred twenty-one".