66717456 has 80 divisors (see below), whose sum is σ = 191654400. Its totient is φ = 19860480.

The previous prime is 66717439. The next prime is 66717463. The reversal of 66717456 is 65471766.

It is a super-2 number, since 2×66717456² = 8902437870223872, which contains 22 as substring.

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, 17620 + ... + 21068.

It is an arithmetic number, because the mean of its divisors is an integer number (2395680).

Almost surely, 2^66717456 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66717456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95827200).

66717456 is an abundant number, since it is smaller than the sum of its proper divisors (124936944).

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

66717456 is a wasteful number, since it uses less digits than its factorization.

66717456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3504 (or 3498 counting only the distinct ones).

The product of its digits is 211680, while the sum is 42.

The square root of 66717456 is about 8168.0754159104. The cubic root of 66717456 is about 405.5830772285.

The spelling of 66717456 in words is "sixty-six million, seven hundred seventeen thousand, four hundred fifty-six".