72139997 has 8 divisors (see below), whose sum is σ = 72932640. Its totient is φ = 71351280.

The previous prime is 72139981. The next prime is 72140009. The reversal of 72139997 is 79993127.

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 72139997 - 2⁴ = 72139981 is a prime.

It is a super-3 number, since 3×72139997³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72139597) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 48923 + ... + 50375.

It is an arithmetic number, because the mean of its divisors is an integer number (9116580).

Almost surely, 2^72139997 is an apocalyptic number.

It is an amenable number.

72139997 is a deficient number, since it is larger than the sum of its proper divisors (792643).

72139997 is a wasteful number, since it uses less digits than its factorization.

72139997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1963.

The product of its digits is 214326, while the sum is 47.

The square root of 72139997 is about 8493.5267704293. The cubic root of 72139997 is about 416.2862247570.

The spelling of 72139997 in words is "seventy-two million, one hundred thirty-nine thousand, nine hundred ninety-seven".