64661140 has 24 divisors (see below), whose sum is σ = 136507392. Its totient is φ = 25727520.

The previous prime is 64661131. The next prime is 64661147. The reversal of 64661140 is 4116646.

It is a junction number, because it is equal to n+sod(n) for n = 64661099 and 64661108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64661147) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4644 + ... + 12283.

It is an arithmetic number, because the mean of its divisors is an integer number (5687808).

Almost surely, 2^64661140 is an apocalyptic number.

It is an amenable number.

64661140 is an abundant number, since it is smaller than the sum of its proper divisors (71846252).

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

64661140 is a wasteful number, since it uses less digits than its factorization.

64661140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17127 (or 17125 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 64661140 is about 8041.2150823119. The cubic root of 64661140 is about 401.3726591290.

Adding to 64661140 its reverse (4116646), we get a palindrome (68777786).

The spelling of 64661140 in words is "sixty-four million, six hundred sixty-one thousand, one hundred forty".