72663661 has 8 divisors (see below), whose sum is σ = 87929280. Its totient is φ = 58619328.

The previous prime is 72663649. The next prime is 72663667. The reversal of 72663661 is 16636627.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 72663661 - 2⁷ = 72663533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72663661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72663667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 305191 + ... + 305428.

It is an arithmetic number, because the mean of its divisors is an integer number (10991160).

Almost surely, 2^72663661 is an apocalyptic number.

It is an amenable number.

72663661 is a deficient number, since it is larger than the sum of its proper divisors (15265619).

72663661 is a wasteful number, since it uses less digits than its factorization.

72663661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 610643.

The product of its digits is 54432, while the sum is 37.

The square root of 72663661 is about 8524.2982702390. The cubic root of 72663661 is about 417.2910707174.

The spelling of 72663661 in words is "seventy-two million, six hundred sixty-three thousand, six hundred sixty-one".