646253040 has 80 divisors (see below), whose sum is σ = 2005898400. Its totient is φ = 172118016.

The previous prime is 646253039. The next prime is 646253051. The reversal of 646253040 is 40352646.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 646252989 and 646253007.

It is a congruent number.

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, 308316 + ... + 310404.

It is an arithmetic number, because the mean of its divisors is an integer number (25073730).

Almost surely, 2^646253040 is an apocalyptic number.

646253040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

646253040 is an abundant number, since it is smaller than the sum of its proper divisors (1359645360).

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

646253040 is a wasteful number, since it uses less digits than its factorization.

646253040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3394 (or 3388 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 646253040 is about 25421.5074297336. The cubic root of 646253040 is about 864.5714027147.

The spelling of 646253040 in words is "six hundred forty-six million, two hundred fifty-three thousand, forty".