72639390 has 64 divisors (see below), whose sum is σ = 179781120. Its totient is φ = 18775680.

The previous prime is 72639379. The next prime is 72639407. The reversal of 72639390 is 9393627.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 142456 + ... + 142964.

It is an arithmetic number, because the mean of its divisors is an integer number (2809080).

Almost surely, 2^72639390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72639390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89890560).

72639390 is an abundant number, since it is smaller than the sum of its proper divisors (107141730).

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

72639390 is a wasteful number, since it uses less digits than its factorization.

72639390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657.

The product of its (nonzero) digits is 61236, while the sum is 39.

The square root of 72639390 is about 8522.8745150917. The cubic root of 72639390 is about 417.2446045778.

It can be divided in two parts, 7263 and 9390, that added together give a triangular number (16653 = T₁₈₂).

The spelling of 72639390 in words is "seventy-two million, six hundred thirty-nine thousand, three hundred ninety".