72774155 has 4 divisors (see below), whose sum is σ = 87328992. Its totient is φ = 58219320.

The previous prime is 72774131. The next prime is 72774167. The reversal of 72774155 is 55147727.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55147727 = 3067 ⋅17981.

It is not a de Polignac number, because 72774155 - 2¹⁶ = 72708619 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7277411 + ... + 7277420.

It is an arithmetic number, because the mean of its divisors is an integer number (21832248).

Almost surely, 2^72774155 is an apocalyptic number.

72774155 is a deficient number, since it is larger than the sum of its proper divisors (14554837).

72774155 is a wasteful number, since it uses less digits than its factorization.

72774155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14554836.

The product of its digits is 68600, while the sum is 38.

The square root of 72774155 is about 8530.7769282756. The cubic root of 72774155 is about 417.5024776647.

The spelling of 72774155 in words is "seventy-two million, seven hundred seventy-four thousand, one hundred fifty-five".