38644240 has 40 divisors (see below), whose sum is σ = 92951640. Its totient is φ = 14923776.

The previous prime is 38644237. The next prime is 38644241. The reversal of 38644240 is 4244683.

38644240 = 623² + 624² + ... + 709².

It can be written as a sum of positive squares in 4 ways, for example, as 15872256 + 22771984 = 3984^2 + 4772^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (38644241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6009 + ... + 10648.

It is an arithmetic number, because the mean of its divisors is an integer number (2323791).

Almost surely, 2^38644240 is an apocalyptic number.

It is an amenable number.

38644240 is an abundant number, since it is smaller than the sum of its proper divisors (54307400).

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

38644240 is a wasteful number, since it uses less digits than its factorization.

38644240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16699 (or 16693 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 31.

The square root of 38644240 is about 6216.4491472222. The cubic root of 38644240 is about 338.0868327260.

The spelling of 38644240 in words is "thirty-eight million, six hundred forty-four thousand, two hundred forty".