156221057 has 8 divisors (see below), whose sum is σ = 161777640. Its totient is φ = 150675840.

The previous prime is 156221053. The next prime is 156221063. The reversal of 156221057 is 750122651.

It can be written as a sum of positive squares in 4 ways, for example, as 495616 + 155725441 = 704^2 + 12479^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 156221057 - 2² = 156221053 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (156221053) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32957 + ... + 37397.

It is an arithmetic number, because the mean of its divisors is an integer number (20222205).

Almost surely, 2^156221057 is an apocalyptic number.

It is an amenable number.

156221057 is a deficient number, since it is larger than the sum of its proper divisors (5556583).

156221057 is a wasteful number, since it uses less digits than its factorization.

156221057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5683.

The product of its (nonzero) digits is 4200, while the sum is 29.

The square root of 156221057 is about 12498.8422263824. The cubic root of 156221057 is about 538.5754140259.

The spelling of 156221057 in words is "one hundred fifty-six million, two hundred twenty-one thousand, fifty-seven".