149157391681 has 9 divisors (see below), whose sum is σ = 149658435649. Its totient is φ = 148658023444.

The previous prime is 149157391679. The next prime is 149157391697. The reversal of 149157391681 is 186193751941.

It is a happy number.

The square root of 149157391681 is 386209.

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

It is not a de Polignac number, because 149157391681 - 2¹ = 149157391679 is a prime.

It is a super-2 number, since 2×149157391681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (149157391651) 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, 180359190 + ... + 180360016.

Almost surely, 2^149157391681 is an apocalyptic number.

149157391681 is the 386209-th square number.

149157391681 is the 193105-th centered octagonal number.

It is an amenable number.

149157391681 is a deficient number, since it is larger than the sum of its proper divisors (501043968).

149157391681 is an frugal number, since it uses more digits than its factorization.

149157391681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2588 (or 1294 counting only the distinct ones).

The product of its digits is 1632960, while the sum is 55.

The spelling of 149157391681 in words is "one hundred forty-nine billion, one hundred fifty-seven million, three hundred ninety-one thousand, six hundred eighty-one".