157765937721 has 32 divisors (see below), whose sum is σ = 248727356160. Its totient is φ = 87031977984.

The previous prime is 157765937711. The next prime is 157765937783. The reversal of 157765937721 is 127739567751.

157765937721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 157765937721 - 2⁵ = 157765937689 is a prime.

It is a super-2 number, since 2×157765937721² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (157765937711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7268541 + ... + 7290213.

It is an arithmetic number, because the mean of its divisors is an integer number (7772729880).

Almost surely, 2^157765937721 is an apocalyptic number.

It is an amenable number.

157765937721 is a deficient number, since it is larger than the sum of its proper divisors (90961418439).

157765937721 is a wasteful number, since it uses less digits than its factorization.

157765937721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33665.

The product of its digits is 19448100, while the sum is 60.

The spelling of 157765937721 in words is "one hundred fifty-seven billion, seven hundred sixty-five million, nine hundred thirty-seven thousand, seven hundred twenty-one".