168621157 has 2 divisors, whose sum is σ = 168621158. Its totient is φ = 168621156.

The previous prime is 168621137. The next prime is 168621163. The reversal of 168621157 is 751126861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125574436 + 43046721 = 11206^2 + 6561^2 .

It is a cyclic number.

It is not a de Polignac number, because 168621157 - 2¹⁹ = 168096869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (168621127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84310578 + 84310579.

It is an arithmetic number, because the mean of its divisors is an integer number (84310579).

Almost surely, 2^168621157 is an apocalyptic number.

It is an amenable number.

168621157 is a deficient number, since it is larger than the sum of its proper divisors (1).

168621157 is an equidigital number, since it uses as much as digits as its factorization.

168621157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20160, while the sum is 37.

The square root of 168621157 is about 12985.4209404239. The cubic root of 168621157 is about 552.4640484923.

The spelling of 168621157 in words is "one hundred sixty-eight million, six hundred twenty-one thousand, one hundred fifty-seven".