72646478 has 4 divisors (see below), whose sum is σ = 108969720. Its totient is φ = 36323238.

The previous prime is 72646471. The next prime is 72646499. The reversal of 72646478 is 87464627.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72646471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18161618 + ... + 18161621.

It is an arithmetic number, because the mean of its divisors is an integer number (27242430).

Almost surely, 2^72646478 is an apocalyptic number.

72646478 is a deficient number, since it is larger than the sum of its proper divisors (36323242).

72646478 is a wasteful number, since it uses less digits than its factorization.

72646478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36323241.

The product of its digits is 451584, while the sum is 44.

The square root of 72646478 is about 8523.2903270979. The cubic root of 72646478 is about 417.2581754222.

The spelling of 72646478 in words is "seventy-two million, six hundred forty-six thousand, four hundred seventy-eight".