66120624 has 100 divisors (see below), whose sum is σ = 193161496. Its totient is φ = 21835008.

The previous prime is 66120617. The next prime is 66120629. The reversal of 66120624 is 42602166.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66120629) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 211092 + ... + 211404.

Almost surely, 2^66120624 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 66120624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96580748).

66120624 is an abundant number, since it is smaller than the sum of its proper divisors (127040872).

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

66120624 is a wasteful number, since it uses less digits than its factorization.

66120624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496 (or 481 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 66120624 is about 8131.4589096914. The cubic root of 66120624 is about 404.3700494685.

It can be divided in two parts, 6612062 and 4, that added together give a triangular number (6612066 = T₃₆₃₆).

The spelling of 66120624 in words is "sixty-six million, one hundred twenty thousand, six hundred twenty-four".