66551974 has 16 divisors (see below), whose sum is σ = 108559008. Its totient is φ = 30471552.

The previous prime is 66551963. The next prime is 66551981. The reversal of 66551974 is 47915566.

It is a self number, because there is not a number n which added to its sum of digits gives 66551974.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25194 + ... + 27709.

It is an arithmetic number, because the mean of its divisors is an integer number (6784938).

Almost surely, 2^66551974 is an apocalyptic number.

66551974 is a deficient number, since it is larger than the sum of its proper divisors (42007034).

66551974 is a wasteful number, since it uses less digits than its factorization.

66551974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52959.

The product of its digits is 226800, while the sum is 43.

The square root of 66551974 is about 8157.9393231379. The cubic root of 66551974 is about 405.2474715757.

The spelling of 66551974 in words is "sixty-six million, five hundred fifty-one thousand, nine hundred seventy-four".