61638966 has 24 divisors (see below), whose sum is σ = 137162064. Its totient is φ = 19990800.

The previous prime is 61638961. The next prime is 61638971. The reversal of 61638966 is 66983616.

61638966 is a `hidden beast` number, since 6 + 1 + 638 + 9 + 6 + 6 = 666.

61638966 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (61638961) and next prime (61638971).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61638961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45610 + ... + 46941.

It is an arithmetic number, because the mean of its divisors is an integer number (5715086).

Almost surely, 2^61638966 is an apocalyptic number.

61638966 is an abundant number, since it is smaller than the sum of its proper divisors (75523098).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61638966 is a wasteful number, since it uses less digits than its factorization.

61638966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92596 (or 92593 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 61638966 is about 7851.0487197571. The cubic root of 61638966 is about 395.0194211463.

It can be divided in two parts, 6163 and 8966, that added together give a square (15129 = 123²).

The spelling of 61638966 in words is "sixty-one million, six hundred thirty-eight thousand, nine hundred sixty-six".