61664024461 has 4 divisors (see below), whose sum is σ = 66407410972. Its totient is φ = 56920637952.

The previous prime is 61664024453. The next prime is 61664024491. The reversal of 61664024461 is 16442046616.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11005268836 + 50658755625 = 104906^2 + 225075^2 .

It is a cyclic number.

It is not a de Polignac number, because 61664024461 - 2³ = 61664024453 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 (61664024431) 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, 2371693236 + ... + 2371693261.

It is an arithmetic number, because the mean of its divisors is an integer number (16601852743).

Almost surely, 2^61664024461 is an apocalyptic number.

It is an amenable number.

61664024461 is a deficient number, since it is larger than the sum of its proper divisors (4743386511).

61664024461 is a wasteful number, since it uses less digits than its factorization.

61664024461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4743386510.

The product of its (nonzero) digits is 165888, while the sum is 40.

The spelling of 61664024461 in words is "sixty-one billion, six hundred sixty-four million, twenty-four thousand, four hundred sixty-one".