66021964 has 6 divisors (see below), whose sum is σ = 115538444. Its totient is φ = 33010980.

The previous prime is 66021961. The next prime is 66021997. The reversal of 66021964 is 46912066.

It is not an unprimeable number, because it can be changed into a prime (66021961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8252742 + ... + 8252749.

Almost surely, 2^66021964 is an apocalyptic number.

It is an amenable number.

66021964 is a deficient number, since it is larger than the sum of its proper divisors (49516480).

66021964 is a wasteful number, since it uses less digits than its factorization.

66021964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16505495 (or 16505493 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 66021964 is about 8125.3900829437. The cubic root of 66021964 is about 404.1688262801.

The spelling of 66021964 in words is "sixty-six million, twenty-one thousand, nine hundred sixty-four".