66871740 has 48 divisors (see below), whose sum is σ = 201646368. Its totient is φ = 16460544.

The previous prime is 66871729. The next prime is 66871747. The reversal of 66871740 is 4717866.

It is a super-2 number, since 2×66871740² = 8943659221255200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66871747) 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, 42087 + ... + 43646.

It is an arithmetic number, because the mean of its divisors is an integer number (4200966).

Almost surely, 2^66871740 is an apocalyptic number.

66871740 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66871740 is an abundant number, since it is smaller than the sum of its proper divisors (134774628).

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

66871740 is a wasteful number, since it uses less digits than its factorization.

66871740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85758 (or 85756 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 39.

The square root of 66871740 is about 8177.5142922529. The cubic root of 66871740 is about 405.8954732653.

The spelling of 66871740 in words is "sixty-six million, eight hundred seventy-one thousand, seven hundred forty".