69664640 has 128 divisors (see below), whose sum is σ = 186170400. Its totient is φ = 24772608.

The previous prime is 69664627. The next prime is 69664643. The reversal of 69664640 is 4646696.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (69664643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 206552 + ... + 206888.

Almost surely, 2^69664640 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 69664640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93085200).

69664640 is an abundant number, since it is smaller than the sum of its proper divisors (116505760).

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

69664640 is a wasteful number, since it uses less digits than its factorization.

69664640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392 (or 380 counting only the distinct ones).

The product of its (nonzero) digits is 186624, while the sum is 41.

The square root of 69664640 is about 8346.5346102439. The cubic root of 69664640 is about 411.4693265036.

The spelling of 69664640 in words is "sixty-nine million, six hundred sixty-four thousand, six hundred forty".