61664100646 has 16 divisors (see below), whose sum is σ = 98835612480. Its totient is φ = 28752174720.

The previous prime is 61664100587. The next prime is 61664100649. The reversal of 61664100646 is 64600146616.

It is a super-2 number, since 2×61664100646² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 61664100599 and 61664100608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61664100649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8315790 + ... + 8323201.

It is an arithmetic number, because the mean of its divisors is an integer number (6177225780).

Almost surely, 2^61664100646 is an apocalyptic number.

61664100646 is a deficient number, since it is larger than the sum of its proper divisors (37171511834).

61664100646 is a wasteful number, since it uses less digits than its factorization.

61664100646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16639119.

The product of its (nonzero) digits is 124416, while the sum is 40.

The spelling of 61664100646 in words is "sixty-one billion, six hundred sixty-four million, one hundred thousand, six hundred forty-six".