1021591157 has 2 divisors, whose sum is σ = 1021591158. Its totient is φ = 1021591156.

The previous prime is 1021591147. The next prime is 1021591163. The reversal of 1021591157 is 7511951201.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1017227236 + 4363921 = 31894^2 + 2089^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021591157 - 2⁶ = 1021591093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021591117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510795578 + 510795579.

It is an arithmetic number, because the mean of its divisors is an integer number (510795579).

Almost surely, 2^1021591157 is an apocalyptic number.

It is an amenable number.

1021591157 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021591157 is an equidigital number, since it uses as much as digits as its factorization.

1021591157 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3150, while the sum is 32.

The square root of 1021591157 is about 31962.3396671771. The cubic root of 1021591157 is about 1007.1458672833.

The spelling of 1021591157 in words is "one billion, twenty-one million, five hundred ninety-one thousand, one hundred fifty-seven".