66719770 has 32 divisors (see below), whose sum is σ = 129901968. Its totient is φ = 24526848.

The previous prime is 66719753. The next prime is 66719771. The reversal of 66719770 is 7791766.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 17397241 + 49322529 = 4171^2 + 7023^2 .

It is not an unprimeable number, because it can be changed into a prime (66719771) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32412 + ... + 34408.

Almost surely, 2^66719770 is an apocalyptic number.

66719770 is a deficient number, since it is larger than the sum of its proper divisors (63182198).

66719770 is a wasteful number, since it uses less digits than its factorization.

66719770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2274.

The product of its (nonzero) digits is 111132, while the sum is 43.

The square root of 66719770 is about 8168.2170637171. The cubic root of 66719770 is about 405.5877661982.

The spelling of 66719770 in words is "sixty-six million, seven hundred nineteen thousand, seven hundred seventy".