63111681 has 6 divisors (see below), whose sum is σ = 91161330. Its totient is φ = 42074448.

The previous prime is 63111613. The next prime is 63111707. The reversal of 63111681 is 18611136.

It can be written as a sum of positive squares in only one way, i.e., 62964225 + 147456 = 7935^2 + 384^2 .

It is not a de Polignac number, because 63111681 - 2¹⁰ = 63110657 is a prime.

It is a super-2 number, since 2×63111681² = 7966168557291522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (63111281) 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, 3506196 + ... + 3506213.

It is an arithmetic number, because the mean of its divisors is an integer number (15193555).

Almost surely, 2^63111681 is an apocalyptic number.

It is an amenable number.

63111681 is a deficient number, since it is larger than the sum of its proper divisors (28049649).

63111681 is a wasteful number, since it uses less digits than its factorization.

63111681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7012415 (or 7012412 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 63111681 is about 7944.2860598042. The cubic root of 63111681 is about 398.1407063754.

The spelling of 63111681 in words is "sixty-three million, one hundred eleven thousand, six hundred eighty-one".