646949520 has 240 divisors, whose sum is σ = 2591476992. Its totient is φ = 141419520.

The previous prime is 646949519. The next prime is 646949531. The reversal of 646949520 is 25949646.

646949520 is a `hidden beast` number, since 64 + 69 + 4 + 9 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 113130 + ... + 118710.

Almost surely, 2^646949520 is an apocalyptic number.

646949520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646949520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1295738496).

646949520 is an abundant number, since it is smaller than the sum of its proper divisors (1944527472).

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

646949520 is a wasteful number, since it uses less digits than its factorization.

646949520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5630 (or 5621 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The square root of 646949520 is about 25435.2023778070. The cubic root of 646949520 is about 864.8818799137.

The spelling of 646949520 in words is "six hundred forty-six million, nine hundred forty-nine thousand, five hundred twenty".