1640253644 has 48 divisors (see below), whose sum is σ = 3001432896. Its totient is φ = 783820800.

The previous prime is 1640253613. The next prime is 1640253661. The reversal of 1640253644 is 4463520461.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1264004 + ... + 1265300.

It is an arithmetic number, because the mean of its divisors is an integer number (62529852).

Almost surely, 2^1640253644 is an apocalyptic number.

It is an amenable number.

1640253644 is a deficient number, since it is larger than the sum of its proper divisors (1361179252).

1640253644 is a wasteful number, since it uses less digits than its factorization.

1640253644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1506 (or 1504 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

The square root of 1640253644 is about 40500.0449876293. The cubic root of 1640253644 is about 1179.3345007342.

The spelling of 1640253644 in words is "one billion, six hundred forty million, two hundred fifty-three thousand, six hundred forty-four".