65638831 has 2 divisors, whose sum is σ = 65638832. Its totient is φ = 65638830.

The previous prime is 65638817. The next prime is 65638843. The reversal of 65638831 is 13883656.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 65638831 - 2⁹ = 65638319 is a prime.

It is a super-2 number, since 2×65638831² = 8616912270093122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (65638891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32819415 + 32819416.

It is an arithmetic number, because the mean of its divisors is an integer number (32819416).

Almost surely, 2^65638831 is an apocalyptic number.

65638831 is a deficient number, since it is larger than the sum of its proper divisors (1).

65638831 is an equidigital number, since it uses as much as digits as its factorization.

65638831 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 40.

The square root of 65638831 is about 8101.7794958885. The cubic root of 65638831 is about 403.3854964446.

The spelling of 65638831 in words is "sixty-five million, six hundred thirty-eight thousand, eight hundred thirty-one".