155324991 has 4 divisors (see below), whose sum is σ = 207099992. Its totient is φ = 103549992.

The previous prime is 155324959. The next prime is 155325011. The reversal of 155324991 is 199423551.

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

It is not a de Polignac number, because 155324991 - 2⁵ = 155324959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155324591) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25887496 + ... + 25887501.

It is an arithmetic number, because the mean of its divisors is an integer number (51774998).

Almost surely, 2^155324991 is an apocalyptic number.

155324991 is a deficient number, since it is larger than the sum of its proper divisors (51775001).

155324991 is an equidigital number, since it uses as much as digits as its factorization.

155324991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51775000.

The product of its digits is 48600, while the sum is 39.

The square root of 155324991 is about 12462.9447162378. The cubic root of 155324991 is about 537.5437033871.

The spelling of 155324991 in words is "one hundred fifty-five million, three hundred twenty-four thousand, nine hundred ninety-one".