66413540 has 24 divisors (see below), whose sum is σ = 139808760. Its totient is φ = 26500608.

The previous prime is 66413539. The next prime is 66413551. The reversal of 66413540 is 4531466.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 9048064 + 57365476 = 3008^2 + 7574^2 .

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, 4826 + ... + 12494.

It is an arithmetic number, because the mean of its divisors is an integer number (5825365).

Almost surely, 2^66413540 is an apocalyptic number.

It is an amenable number.

66413540 is an abundant number, since it is smaller than the sum of its proper divisors (73395220).

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

66413540 is a wasteful number, since it uses less digits than its factorization.

66413540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8111 (or 8109 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 66413540 is about 8149.4502882096. The cubic root of 66413540 is about 404.9662929830.

The spelling of 66413540 in words is "sixty-six million, four hundred thirteen thousand, five hundred forty".