155388431 has 4 divisors (see below), whose sum is σ = 169514664. Its totient is φ = 141262200.

The previous prime is 155388397. The next prime is 155388433. The reversal of 155388431 is 134883551.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 155388431 - 2¹⁴ = 155372047 is a prime.

It is a super-2 number, since 2×155388431² = 48291128977283522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155388433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7063100 + ... + 7063121.

It is an arithmetic number, because the mean of its divisors is an integer number (42378666).

Almost surely, 2^155388431 is an apocalyptic number.

155388431 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

155388431 is a deficient number, since it is larger than the sum of its proper divisors (14126233).

155388431 is a wasteful number, since it uses less digits than its factorization.

155388431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14126232.

The product of its digits is 57600, while the sum is 38.

The square root of 155388431 is about 12465.4896012952. The cubic root of 155388431 is about 537.6168771256.

The spelling of 155388431 in words is "one hundred fifty-five million, three hundred eighty-eight thousand, four hundred thirty-one".