64161631 has 4 divisors (see below), whose sum is σ = 64191064. Its totient is φ = 64132200.

The previous prime is 64161607. The next prime is 64161637. The reversal of 64161631 is 13616146.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13616146 = 2 ⋅6808073.

It is a cyclic number.

It is not a de Polignac number, because 64161631 - 2¹⁷ = 64030559 is a prime.

It is a super-2 number, since 2×64161631² = 8233429785160322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64161631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64161637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11160 + ... + 15901.

It is an arithmetic number, because the mean of its divisors is an integer number (16047766).

Almost surely, 2^64161631 is an apocalyptic number.

64161631 is a deficient number, since it is larger than the sum of its proper divisors (29433).

64161631 is a wasteful number, since it uses less digits than its factorization.

64161631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29432.

The product of its digits is 2592, while the sum is 28.

The square root of 64161631 is about 8010.0955674698. The cubic root of 64161631 is about 400.3364481772.

Adding to 64161631 its reverse (13616146), we get a palindrome (77777777).

The spelling of 64161631 in words is "sixty-four million, one hundred sixty-one thousand, six hundred thirty-one".