63720139 has 10 divisors (see below), whose sum is σ = 74338540. Its totient is φ = 54615204.

The previous prime is 63720127. The next prime is 63720161. The reversal of 63720139 is 93102736.

It is not a de Polignac number, because 63720139 - 2⁷ = 63720011 is a prime.

It is a super-2 number, since 2×63720139² = 8120512228358642, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 63720139.

It is not an unprimeable number, because it can be changed into a prime (63720119) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 10869 + ... + 15670.

It is an arithmetic number, because the mean of its divisors is an integer number (7433854).

Almost surely, 2^63720139 is an apocalyptic number.

63720139 is a deficient number, since it is larger than the sum of its proper divisors (10618401).

63720139 is an frugal number, since it uses more digits than its factorization.

63720139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26567 (or 26546 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 31.

The square root of 63720139 is about 7982.4895239518. The cubic root of 63720139 is about 399.4161043293.

The spelling of 63720139 in words is "sixty-three million, seven hundred twenty thousand, one hundred thirty-nine".