63720639 has 6 divisors (see below), whose sum is σ = 92040936. Its totient is φ = 42480420.

The previous prime is 63720619. The next prime is 63720667. The reversal of 63720639 is 93602736.

It is not a de Polignac number, because 63720639 - 2⁹ = 63720127 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63720619) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3540027 + ... + 3540044.

It is an arithmetic number, because the mean of its divisors is an integer number (15340156).

Almost surely, 2^63720639 is an apocalyptic number.

63720639 is a deficient number, since it is larger than the sum of its proper divisors (28320297).

63720639 is a wasteful number, since it uses less digits than its factorization.

63720639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7080077 (or 7080074 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 36.

The square root of 63720639 is about 7982.5208424407. The cubic root of 63720639 is about 399.4171490411.

The spelling of 63720639 in words is "sixty-three million, seven hundred twenty thousand, six hundred thirty-nine".