66687072 has 48 divisors (see below), whose sum is σ = 176687280. Its totient is φ = 22021632.

The previous prime is 66687067. The next prime is 66687083. The reversal of 66687072 is 27078666.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

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, 7278 + ... + 13650.

It is an arithmetic number, because the mean of its divisors is an integer number (3680985).

Almost surely, 2^66687072 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 66687072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88343640).

66687072 is an abundant number, since it is smaller than the sum of its proper divisors (110000208).

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

66687072 is a wasteful number, since it uses less digits than its factorization.

66687072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6495 (or 6487 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 42.

The square root of 66687072 is about 8166.2152800425. The cubic root of 66687072 is about 405.5214986045.

The spelling of 66687072 in words is "sixty-six million, six hundred eighty-seven thousand, seventy-two".