156381493401 has 45 divisors (see below), whose sum is σ = 271790127279. Its totient is φ = 89346617136.

The previous prime is 156381493363. The next prime is 156381493403. The reversal of 156381493401 is 104394183651.

The square root of 156381493401 is 395451.

It is a perfect power (a square), and thus also a powerful number.

156381493401 is a `hidden beast` number, since 1 + 5 + 638 + 1 + 4 + 9 + 3 + 4 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 152814537225 + 3566956176 = 390915^2 + 59724^2 .

It is not a de Polignac number, because 156381493401 - 2²⁷ = 156247275673 is a prime.

It is not an unprimeable number, because it can be changed into a prime (156381493403) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 24910275 + ... + 24916551.

Almost surely, 2^156381493401 is an apocalyptic number.

156381493401 is the 395451-st square number.

156381493401 is the 197726-th centered octagonal number.

It is an amenable number.

156381493401 is a deficient number, since it is larger than the sum of its proper divisors (115408633878).

156381493401 is an frugal number, since it uses more digits than its factorization.

156381493401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12580 (or 6287 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The spelling of 156381493401 in words is "one hundred fifty-six billion, three hundred eighty-one million, four hundred ninety-three thousand, four hundred one".