66912642 has 40 divisors (see below), whose sum is σ = 157832400. Its totient is φ = 21129336.

The previous prime is 66912607. The next prime is 66912647. The reversal of 66912642 is 24621966.

66912642 is a `hidden beast` number, since 6 + 6 + 9 + 1 + 2 + 642 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 66912597 and 66912606.

It is not an unprimeable number, because it can be changed into a prime (66912647) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7792 + ... + 13947.

It is an arithmetic number, because the mean of its divisors is an integer number (3945810).

Almost surely, 2^66912642 is an apocalyptic number.

66912642 is an abundant number, since it is smaller than the sum of its proper divisors (90919758).

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

66912642 is a wasteful number, since it uses less digits than its factorization.

66912642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21772 (or 21763 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 66912642 is about 8180.0147921627. The cubic root of 66912642 is about 405.9782115189.

The spelling of 66912642 in words is "sixty-six million, nine hundred twelve thousand, six hundred forty-two".