66461772 has 96 divisors (see below), whose sum is σ = 186278400. Its totient is φ = 18220032.

The previous prime is 66461771. The next prime is 66461849. The reversal of 66461772 is 27716466.

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

It is a self number, because there is not a number n which added to its sum of digits gives 66461772.

It is not an unprimeable number, because it can be changed into a prime (66461771) 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, 49729 + ... + 51047.

It is an arithmetic number, because the mean of its divisors is an integer number (1940400).

Almost surely, 2^66461772 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 66461772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93139200).

66461772 is an abundant number, since it is smaller than the sum of its proper divisors (119816628).

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

66461772 is a wasteful number, since it uses less digits than its factorization.

66461772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1375 (or 1373 counting only the distinct ones).

The product of its digits is 84672, while the sum is 39.

The square root of 66461772 is about 8152.4089691330. The cubic root of 66461772 is about 405.0643031567.

The spelling of 66461772 in words is "sixty-six million, four hundred sixty-one thousand, seven hundred seventy-two".