63959621 has 16 divisors (see below), whose sum is σ = 71739648. Its totient is φ = 56524800.

The previous prime is 63959617. The next prime is 63959639. The reversal of 63959621 is 12695936.

It is a cyclic number.

It is not a de Polignac number, because 63959621 - 2² = 63959617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63959641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 99461 + ... + 100101.

It is an arithmetic number, because the mean of its divisors is an integer number (4483728).

Almost surely, 2^63959621 is an apocalyptic number.

It is an amenable number.

63959621 is a deficient number, since it is larger than the sum of its proper divisors (7780027).

63959621 is a wasteful number, since it uses less digits than its factorization.

63959621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 892.

The product of its digits is 87480, while the sum is 41.

The square root of 63959621 is about 7997.4759143120. The cubic root of 63959621 is about 399.9158593855.

The spelling of 63959621 in words is "sixty-three million, nine hundred fifty-nine thousand, six hundred twenty-one".