157890521 has 2 divisors, whose sum is σ = 157890522. Its totient is φ = 157890520.

The previous prime is 157890461. The next prime is 157890547. The reversal of 157890521 is 125098751.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80802121 + 77088400 = 8989^2 + 8780^2 .

It is a cyclic number.

It is not a de Polignac number, because 157890521 - 2⁶ = 157890457 is a prime.

It is not a weakly prime, because it can be changed into another prime (157892521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78945260 + 78945261.

It is an arithmetic number, because the mean of its divisors is an integer number (78945261).

Almost surely, 2^157890521 is an apocalyptic number.

It is an amenable number.

157890521 is a deficient number, since it is larger than the sum of its proper divisors (1).

157890521 is an equidigital number, since it uses as much as digits as its factorization.

157890521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25200, while the sum is 38.

The square root of 157890521 is about 12565.4494945465. The cubic root of 157890521 is about 540.4871244561.

The spelling of 157890521 in words is "one hundred fifty-seven million, eight hundred ninety thousand, five hundred twenty-one".