66398574 has 64 divisors (see below), whose sum is σ = 151683840. Its totient is φ = 19192320.

The previous prime is 66398573. The next prime is 66398593. The reversal of 66398574 is 47589366.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66398573) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 216129 + ... + 216435.

It is an arithmetic number, because the mean of its divisors is an integer number (2370060).

Almost surely, 2^66398574 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66398574, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75841920).

66398574 is an abundant number, since it is smaller than the sum of its proper divisors (85285266).

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

66398574 is a wasteful number, since it uses less digits than its factorization.

66398574 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 465.

The product of its digits is 1088640, while the sum is 48.

The square root of 66398574 is about 8148.5320150319. The cubic root of 66398574 is about 404.9358715717.

The spelling of 66398574 in words is "sixty-six million, three hundred ninety-eight thousand, five hundred seventy-four".