155421297 has 18 divisors (see below), whose sum is σ = 226193942. Its totient is φ = 102836736.

The previous prime is 155421289. The next prime is 155421319. The reversal of 155421297 is 792124551.

155421297 is a `hidden beast` number, since 1 + 554 + 2 + 12 + 97 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 137452176 + 17969121 = 11724^2 + 4239^2 .

It is not a de Polignac number, because 155421297 - 2³ = 155421289 is a prime.

It is a super-2 number, since 2×155421297² = 48311559122324418, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155421397) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 269073 + ... + 269649.

Almost surely, 2^155421297 is an apocalyptic number.

It is an amenable number.

155421297 is a deficient number, since it is larger than the sum of its proper divisors (70772645).

155421297 is an equidigital number, since it uses as much as digits as its factorization.

155421297 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 929 (or 753 counting only the distinct ones).

The product of its digits is 25200, while the sum is 36.

The square root of 155421297 is about 12466.8078111440. The cubic root of 155421297 is about 537.6547779968.

The spelling of 155421297 in words is "one hundred fifty-five million, four hundred twenty-one thousand, two hundred ninety-seven".