697791244921 has 9 divisors (see below), whose sum is σ = 707542803279. Its totient is φ = 688172316336.

The previous prime is 697791244879. The next prime is 697791244973. The reversal of 697791244921 is 129442197796.

The square root of 697791244921 is 835339.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 396100303225 + 301690941696 = 629365^2 + 549264^2 .

It is not a de Polignac number, because 697791244921 - 2¹¹ = 697791242873 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 697791244921.

It is not an unprimeable number, because it can be changed into a prime (697791241921) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 60974026 + ... + 60985468.

It is an arithmetic number, because the mean of its divisors is an integer number (78615867031).

Almost surely, 2^697791244921 is an apocalyptic number.

697791244921 is the 835339-th square number.

697791244921 is the 417670-th centered octagonal number.

It is an amenable number.

697791244921 is a deficient number, since it is larger than the sum of its proper divisors (9751558358).

697791244921 is an frugal number, since it uses more digits than its factorization.

697791244921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23032 (or 11516 counting only the distinct ones).

The product of its digits is 13716864, while the sum is 61.

The spelling of 697791244921 in words is "six hundred ninety-seven billion, seven hundred ninety-one million, two hundred forty-four thousand, nine hundred twenty-one".