72747551 has 6 divisors (see below), whose sum is σ = 76048560. Its totient is φ = 69584108.

The previous prime is 72747547. The next prime is 72747557. The reversal of 72747551 is 15574727.

It is not a de Polignac number, because 72747551 - 2² = 72747547 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 (72747557) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 68231 + ... + 69288.

It is an arithmetic number, because the mean of its divisors is an integer number (12674760).

Almost surely, 2^72747551 is an apocalyptic number.

72747551 is a deficient number, since it is larger than the sum of its proper divisors (3301009).

72747551 is a wasteful number, since it uses less digits than its factorization.

72747551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137565 (or 137542 counting only the distinct ones).

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

The square root of 72747551 is about 8529.2174904853. The cubic root of 72747551 is about 417.4515960952.

The spelling of 72747551 in words is "seventy-two million, seven hundred forty-seven thousand, five hundred fifty-one".