72121775 has 12 divisors (see below), whose sum is σ = 97561464. Its totient is φ = 52452000.

The previous prime is 72121757. The next prime is 72121787. The reversal of 72121775 is 57712127.

It is not a de Polignac number, because 72121775 - 2⁸ = 72121519 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 130856 + ... + 131405.

It is an arithmetic number, because the mean of its divisors is an integer number (8130122).

Almost surely, 2^72121775 is an apocalyptic number.

72121775 is a deficient number, since it is larger than the sum of its proper divisors (25439689).

72121775 is a wasteful number, since it uses less digits than its factorization.

72121775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 262282 (or 262277 counting only the distinct ones).

The product of its digits is 6860, while the sum is 32.

The square root of 72121775 is about 8492.4540034080. The cubic root of 72121775 is about 416.2511715887.

The spelling of 72121775 in words is "seventy-two million, one hundred twenty-one thousand, seven hundred seventy-five".