157221601 has 4 divisors (see below), whose sum is σ = 157393600. Its totient is φ = 157049604.

The previous prime is 157221551. The next prime is 157221641. The reversal of 157221601 is 106122751.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 157221601 - 2¹⁵ = 157188833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (157221641) 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 in 3 ways as a sum of consecutive naturals, for example, 84621 + ... + 86458.

It is an arithmetic number, because the mean of its divisors is an integer number (39348400).

Almost surely, 2^157221601 is an apocalyptic number.

It is an amenable number.

157221601 is a deficient number, since it is larger than the sum of its proper divisors (171999).

157221601 is an equidigital number, since it uses as much as digits as its factorization.

157221601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171998.

The product of its (nonzero) digits is 840, while the sum is 25.

The square root of 157221601 is about 12538.8038105714. The cubic root of 157221601 is about 539.7227669308.

The spelling of 157221601 in words is "one hundred fifty-seven million, two hundred twenty-one thousand, six hundred one".