1397771172521 has 16 divisors (see below), whose sum is σ = 1457428023360. Its totient is φ = 1338907631040.

The previous prime is 1397771172431. The next prime is 1397771172527. The reversal of 1397771172521 is 1252711777931.

It is a cyclic number.

It is not a de Polignac number, because 1397771172521 - 2²² = 1397766978217 is a prime.

It is a super-2 number, since 2×1397771172521² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1397771172527) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2398691 + ... + 2923911.

It is an arithmetic number, because the mean of its divisors is an integer number (91089251460).

Almost surely, 2^{1397771172521} is an apocalyptic number.

It is an amenable number.

1397771172521 is a deficient number, since it is larger than the sum of its proper divisors (59656850839).

1397771172521 is a wasteful number, since it uses less digits than its factorization.

1397771172521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525976.

The product of its digits is 1296540, while the sum is 53.

The spelling of 1397771172521 in words is "one trillion, three hundred ninety-seven billion, seven hundred seventy-one million, one hundred seventy-two thousand, five hundred twenty-one".