72426640 has 120 divisors (see below), whose sum is σ = 199326528. Its totient is φ = 24261120.

The previous prime is 72426631. The next prime is 72426661. The reversal of 72426640 is 4662427.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 148477 + ... + 148963.

Almost surely, 2^72426640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72426640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99663264).

72426640 is an abundant number, since it is smaller than the sum of its proper divisors (126899888).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72426640 is a wasteful number, since it uses less digits than its factorization.

72426640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 537 (or 518 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 72426640 is about 8510.3842451443. The cubic root of 72426640 is about 416.8368570529.

The spelling of 72426640 in words is "seventy-two million, four hundred twenty-six thousand, six hundred forty".