66997632 has 64 divisors (see below), whose sum is σ = 191666160. Its totient is φ = 20613120.

The previous prime is 66997577. The next prime is 66997661. The reversal of 66997632 is 23679966.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-3 number, since 3×66997632³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1719 + ... + 11702.

Almost surely, 2^66997632 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 66997632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95833080).

66997632 is an abundant number, since it is smaller than the sum of its proper divisors (124668528).

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

66997632 is a wasteful number, since it uses less digits than its factorization.

66997632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13451 (or 13439 counting only the distinct ones).

The product of its digits is 734832, while the sum is 48.

The square root of 66997632 is about 8185.2081219722. The cubic root of 66997632 is about 406.1500250400.

The spelling of 66997632 in words is "sixty-six million, nine hundred ninety-seven thousand, six hundred thirty-two".