63971557 has 16 divisors (see below), whose sum is σ = 71245440. Its totient is φ = 57056832.

The previous prime is 63971543. The next prime is 63971563. The reversal of 63971557 is 75517936.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-63971557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63971657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85728 + ... + 86470.

It is an arithmetic number, because the mean of its divisors is an integer number (4452840).

Almost surely, 2^63971557 is an apocalyptic number.

It is an amenable number.

63971557 is a deficient number, since it is larger than the sum of its proper divisors (7273883).

63971557 is a wasteful number, since it uses less digits than its factorization.

63971557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 972.

The product of its digits is 198450, while the sum is 43.

The square root of 63971557 is about 7998.2221149453. Note that the first 3 decimals coincide. The cubic root of 63971557 is about 399.9407349696.

The spelling of 63971557 in words is "sixty-three million, nine hundred seventy-one thousand, five hundred fifty-seven".