157121819 has 2 divisors, whose sum is σ = 157121820. Its totient is φ = 157121818.

The previous prime is 157121813. The next prime is 157121851. The reversal of 157121819 is 918121751.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-157121819 is a prime.

It is a super-2 number, since 2×157121819² = 49374532011737522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (157121813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78560909 + 78560910.

It is an arithmetic number, because the mean of its divisors is an integer number (78560910).

Almost surely, 2^157121819 is an apocalyptic number.

157121819 is a deficient number, since it is larger than the sum of its proper divisors (1).

157121819 is an equidigital number, since it uses as much as digits as its factorization.

157121819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5040, while the sum is 35.

The square root of 157121819 is about 12534.8242508621. The cubic root of 157121819 is about 539.6085629158.

The spelling of 157121819 in words is "one hundred fifty-seven million, one hundred twenty-one thousand, eight hundred nineteen".