157366212721 has 2 divisors, whose sum is σ = 157366212722. Its totient is φ = 157366212720.

The previous prime is 157366212691. The next prime is 157366212737. The reversal of 157366212721 is 127212663751.

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., 93336971121 + 64029241600 = 305511^2 + 253040^2 .

It is an emirp because it is prime and its reverse (127212663751) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 157366212721 - 2⁷ = 157366212593 is a prime.

It is not a weakly prime, because it can be changed into another prime (157366212821) 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, 78683106360 + 78683106361.

It is an arithmetic number, because the mean of its divisors is an integer number (78683106361).

Almost surely, 2^157366212721 is an apocalyptic number.

It is an amenable number.

157366212721 is a deficient number, since it is larger than the sum of its proper divisors (1).

157366212721 is an equidigital number, since it uses as much as digits as its factorization.

157366212721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 211680, while the sum is 43.

The spelling of 157366212721 in words is "one hundred fifty-seven billion, three hundred sixty-six million, two hundred twelve thousand, seven hundred twenty-one".