72686655 has 24 divisors (see below), whose sum is σ = 126191520. Its totient is φ = 38704320.

The previous prime is 72686651. The next prime is 72686657. The reversal of 72686655 is 55668627.

It is not a de Polignac number, because 72686655 - 2² = 72686651 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 72686655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72686651) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 47350 + ... + 48860.

It is an arithmetic number, because the mean of its divisors is an integer number (5257980).

Almost surely, 2^72686655 is an apocalyptic number.

72686655 is a deficient number, since it is larger than the sum of its proper divisors (53504865).

72686655 is a wasteful number, since it uses less digits than its factorization.

72686655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2591 (or 2588 counting only the distinct ones).

The product of its digits is 604800, while the sum is 45.

The square root of 72686655 is about 8525.6468962771. The cubic root of 72686655 is about 417.3350825330.

The spelling of 72686655 in words is "seventy-two million, six hundred eighty-six thousand, six hundred fifty-five".