66421970 has 16 divisors (see below), whose sum is σ = 121198680. Its totient is φ = 26204544.

The previous prime is 66421931. The next prime is 66421981. The reversal of 66421970 is 7912466.

It can be written as a sum of positive squares in 4 ways, for example, as 60016009 + 6405961 = 7747^2 + 2531^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66421970.

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, 44765 + ... + 46224.

Almost surely, 2^66421970 is an apocalyptic number.

66421970 is a deficient number, since it is larger than the sum of its proper divisors (54776710).

66421970 is a wasteful number, since it uses less digits than its factorization.

66421970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91069.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 66421970 is about 8149.9674845977. The cubic root of 66421970 is about 404.9834266449.

The spelling of 66421970 in words is "sixty-six million, four hundred twenty-one thousand, nine hundred seventy".