66117564 has 36 divisors (see below), whose sum is σ = 172896360. Its totient is φ = 21278880.

The previous prime is 66117559. The next prime is 66117589. The reversal of 66117564 is 46571166.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 30622 + ... + 32709.

Almost surely, 2^66117564 is an apocalyptic number.

It is an amenable number.

66117564 is an abundant number, since it is smaller than the sum of its proper divisors (106778796).

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

66117564 is a wasteful number, since it uses less digits than its factorization.

66117564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63370 (or 63365 counting only the distinct ones).

The product of its digits is 30240, while the sum is 36.

The square root of 66117564 is about 8131.2707493970. The cubic root of 66117564 is about 404.3638114177.

It can be divided in two parts, 661 and 17564, that added together give a square (18225 = 135²).

The spelling of 66117564 in words is "sixty-six million, one hundred seventeen thousand, five hundred sixty-four".