157133721 has 8 divisors (see below), whose sum is σ = 212462784. Its totient is φ = 103280240.

The previous prime is 157133707. The next prime is 157133747. The reversal of 157133721 is 127331751.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 157133721 - 2⁹ = 157133209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (157132721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 368646 + ... + 369071.

It is an arithmetic number, because the mean of its divisors is an integer number (26557848).

Almost surely, 2^157133721 is an apocalyptic number.

It is an amenable number.

157133721 is a deficient number, since it is larger than the sum of its proper divisors (55329063).

157133721 is an equidigital number, since it uses as much as digits as its factorization.

157133721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 737791.

The product of its digits is 4410, while the sum is 30.

The square root of 157133721 is about 12535.2989992261. The cubic root of 157133721 is about 539.6221877134.

The spelling of 157133721 in words is "one hundred fifty-seven million, one hundred thirty-three thousand, seven hundred twenty-one".