156254221 has 2 divisors, whose sum is σ = 156254222. Its totient is φ = 156254220.

The previous prime is 156254183. The next prime is 156254269. The reversal of 156254221 is 122452651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 155900196 + 354025 = 12486^2 + 595^2 .

It is an emirp because it is prime and its reverse (122452651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 156254221 - 2¹⁵ = 156221453 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 156254221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (156254621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78127110 + 78127111.

It is an arithmetic number, because the mean of its divisors is an integer number (78127111).

Almost surely, 2^156254221 is an apocalyptic number.

It is an amenable number.

156254221 is a deficient number, since it is larger than the sum of its proper divisors (1).

156254221 is an equidigital number, since it uses as much as digits as its factorization.

156254221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4800, while the sum is 28.

The square root of 156254221 is about 12500.1688388597. The cubic root of 156254221 is about 538.6135225277.

The spelling of 156254221 in words is "one hundred fifty-six million, two hundred fifty-four thousand, two hundred twenty-one".