66397758 has 32 divisors (see below), whose sum is σ = 155871744. Its totient is φ = 18457632.

The previous prime is 66397739. The next prime is 66397763. The reversal of 66397758 is 85779366.

It is a self number, because there is not a number n which added to its sum of digits gives 66397758.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19810 + ... + 22917.

It is an arithmetic number, because the mean of its divisors is an integer number (4870992).

Almost surely, 2^66397758 is an apocalyptic number.

66397758 is an abundant number, since it is smaller than the sum of its proper divisors (89473986).

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

66397758 is a wasteful number, since it uses less digits than its factorization.

66397758 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42776.

The product of its digits is 1905120, while the sum is 51.

The square root of 66397758 is about 8148.4819445097. The cubic root of 66397758 is about 404.9342127558.

The spelling of 66397758 in words is "sixty-six million, three hundred ninety-seven thousand, seven hundred fifty-eight".