157626995491681 has 27 divisors (see below), whose sum is σ = 170248649060217. Its totient is φ = 145910720307840.

The previous prime is 157626995491657. The next prime is 157626995491687. The reversal of 157626995491681 is 186194599626751.

The square root of 157626995491681 is 12554959.

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

It can be written as a sum of positive squares in 4 ways, for example, as 14544345827025 + 143082649664656 = 3813705^2 + 11961716^2 .

It is not a de Polignac number, because 157626995491681 - 2²¹ = 157626993394529 is a prime.

It is a super-2 number, since 2×157626995491681² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157626995491687) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 13019486430 + ... + 13019498536.

Almost surely, 2^{157626995491681} is an apocalyptic number.

157626995491681 is the 12554959-th square number.

157626995491681 is the 6277480-th centered octagonal number.

It is an amenable number.

157626995491681 is a deficient number, since it is larger than the sum of its proper divisors (12621653568536).

157626995491681 is an frugal number, since it uses more digits than its factorization.

157626995491681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24370 (or 12185 counting only the distinct ones).

The product of its digits is 1763596800, while the sum is 79.

The spelling of 157626995491681 in words is "one hundred fifty-seven trillion, six hundred twenty-six billion, nine hundred ninety-five million, four hundred ninety-one thousand, six hundred eighty-one".