649393920 has 216 divisors, whose sum is σ = 2568130656. Its totient is φ = 148414464.

The previous prime is 649393883. The next prime is 649393939. The reversal of 649393920 is 29393946.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 76614 + ... + 84666.

Almost surely, 2^649393920 is an apocalyptic number.

649393920 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 649393920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1284065328).

649393920 is an abundant number, since it is smaller than the sum of its proper divisors (1918736736).

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

649393920 is a wasteful number, since it uses less digits than its factorization.

649393920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8087 (or 8070 counting only the distinct ones).

The product of its (nonzero) digits is 314928, while the sum is 45.

The square root of 649393920 is about 25483.2085891867. The cubic root of 649393920 is about 865.9697856178.

The spelling of 649393920 in words is "six hundred forty-nine million, three hundred ninety-three thousand, nine hundred twenty".