351697627681 has 3 divisors (see below), whose sum is σ = 351698220723. Its totient is φ = 351697034640.

The previous prime is 351697627667. The next prime is 351697627691. The reversal of 351697627681 is 186726796153.

It is a happy number.

The square root of 351697627681 is 593041.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 149737267681 + 201960360000 = 386959^2 + 449400^2 .

It is not a de Polignac number, because 351697627681 - 2¹¹ = 351697625633 is a prime.

It is a super-2 number, since 2×351697627681² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (351697627691) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 296521 + ... + 889561.

It is an arithmetic number, because the mean of its divisors is an integer number (117232740241).

Almost surely, 2^351697627681 is an apocalyptic number.

351697627681 is the 593041-st square number.

351697627681 is the 296521-st centered octagonal number.

It is an amenable number.

351697627681 is a deficient number, since it is larger than the sum of its proper divisors (593042).

351697627681 is an frugal number, since it uses more digits than its factorization.

351697627681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1186082 (or 593041 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 61.

The spelling of 351697627681 in words is "three hundred fifty-one billion, six hundred ninety-seven million, six hundred twenty-seven thousand, six hundred eighty-one".