66612736 has 40 divisors (see below), whose sum is σ = 133857504. Its totient is φ = 33116160.

The previous prime is 66612731. The next prime is 66612737. The reversal of 66612736 is 63721666.

66612736 = T₂₈₈ + T₂₈₉ + ... + T₇₅₀.

It is a super-4 number, since 4×66612736⁴ (a number of 32 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66612695 and 66612704.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66612731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143641 + ... + 144103.

Almost surely, 2^66612736 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 66612736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66928752).

66612736 is an abundant number, since it is smaller than the sum of its proper divisors (67244768).

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

66612736 is an equidigital number, since it uses as much as digits as its factorization.

66612736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762 (or 746 counting only the distinct ones).

The product of its digits is 54432, while the sum is 37.

The square root of 66612736 is about 8161.6625757256. The cubic root of 66612736 is about 405.3707644719.

The spelling of 66612736 in words is "sixty-six million, six hundred twelve thousand, seven hundred thirty-six".