63766981 has 2 divisors, whose sum is σ = 63766982. Its totient is φ = 63766980.

The previous prime is 63766957. The next prime is 63766993. The reversal of 63766981 is 18966736.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59213025 + 4553956 = 7695^2 + 2134^2 .

It is a cyclic number.

It is not a de Polignac number, because 63766981 - 2¹⁷ = 63635909 is a prime.

It is a super-2 number, since 2×63766981² = 8132455731708722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (63767981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 31883490 + 31883491.

It is an arithmetic number, because the mean of its divisors is an integer number (31883491).

Almost surely, 2^63766981 is an apocalyptic number.

It is an amenable number.

63766981 is a deficient number, since it is larger than the sum of its proper divisors (1).

63766981 is an equidigital number, since it uses as much as digits as its factorization.

63766981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 46.

The square root of 63766981 is about 7985.4230320002. The cubic root of 63766981 is about 399.5139533859.

The spelling of 63766981 in words is "sixty-three million, seven hundred sixty-six thousand, nine hundred eighty-one".