72780638 has 32 divisors (see below), whose sum is σ = 132663744. Its totient is φ = 29233152.

The previous prime is 72780629. The next prime is 72780649. The reversal of 72780638 is 83608727.

It is a junction number, because it is equal to n+sod(n) for n = 72780595 and 72780604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74006 + ... + 74982.

It is an arithmetic number, because the mean of its divisors is an integer number (4145742).

Almost surely, 2^72780638 is an apocalyptic number.

72780638 is a deficient number, since it is larger than the sum of its proper divisors (59883106).

72780638 is a wasteful number, since it uses less digits than its factorization.

72780638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1316.

The product of its (nonzero) digits is 112896, while the sum is 41.

The square root of 72780638 is about 8531.1568969279. The cubic root of 72780638 is about 417.5148748689.

The spelling of 72780638 in words is "seventy-two million, seven hundred eighty thousand, six hundred thirty-eight".