70644640 has 144 divisors (see below), whose sum is σ = 190035720. Its totient is φ = 24780800.

The previous prime is 70644631. The next prime is 70644647. The reversal of 70644640 is 4644607.

It can be written as a sum of positive squares in 4 ways, for example, as 26501904 + 44142736 = 5148^2 + 6644^2 .

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70644647) 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 23 ways as a sum of consecutive naturals, for example, 793716 + ... + 793804.

Almost surely, 2^70644640 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 70644640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95017860).

70644640 is an abundant number, since it is smaller than the sum of its proper divisors (119391080).

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

70644640 is a wasteful number, since it uses less digits than its factorization.

70644640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 31.

The square root of 70644640 is about 8405.0365852862. The cubic root of 70644640 is about 413.3897830175.

The spelling of 70644640 in words is "seventy million, six hundred forty-four thousand, six hundred forty".