157890091 has 2 divisors, whose sum is σ = 157890092. Its totient is φ = 157890090.

The previous prime is 157890079. The next prime is 157890107. The reversal of 157890091 is 190098751.

It is a happy number.

157890091 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is an emirp because it is prime and its reverse (190098751) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 157890091 - 2⁵ = 157890059 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (157890001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78945045 + 78945046.

It is an arithmetic number, because the mean of its divisors is an integer number (78945046).

Almost surely, 2^157890091 is an apocalyptic number.

157890091 is a deficient number, since it is larger than the sum of its proper divisors (1).

157890091 is an equidigital number, since it uses as much as digits as its factorization.

157890091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22680, while the sum is 40.

The square root of 157890091 is about 12565.4323841243. The cubic root of 157890091 is about 540.4866338004.

The spelling of 157890091 in words is "one hundred fifty-seven million, eight hundred ninety thousand, ninety-one".