72155511 has 12 divisors (see below), whose sum is σ = 105257880. Its totient is φ = 47626800.

The previous prime is 72155491. The next prime is 72155537. The reversal of 72155511 is 11555127.

It is not a de Polignac number, because 72155511 - 2¹⁴ = 72139127 is a prime.

It is a super-2 number, since 2×72155511² = 10412835535342242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72195511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38781 + ... + 40598.

It is an arithmetic number, because the mean of its divisors is an integer number (8771490).

Almost surely, 2^72155511 is an apocalyptic number.

72155511 is a deficient number, since it is larger than the sum of its proper divisors (33102369).

72155511 is a wasteful number, since it uses less digits than its factorization.

72155511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79486 (or 79483 counting only the distinct ones).

The product of its digits is 1750, while the sum is 27.

The square root of 72155511 is about 8494.4400050857. The cubic root of 72155511 is about 416.3160639671.

The spelling of 72155511 in words is "seventy-two million, one hundred fifty-five thousand, five hundred eleven".