651387840 has 112 divisors (see below), whose sum is σ = 2073432480. Its totient is φ = 173260800.

The previous prime is 651387823. The next prime is 651387857. The reversal of 651387840 is 48783156.

It is an interprime number because it is at equal distance from previous prime (651387823) and next prime (651387857).

It is a super-2 number, since 2×651387840² = 848612236199731200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 651387792 and 651387801.

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, 576396 + ... + 577524.

It is an arithmetic number, because the mean of its divisors is an integer number (18512790).

Almost surely, 2^651387840 is an apocalyptic number.

651387840 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 651387840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1036716240).

651387840 is an abundant number, since it is smaller than the sum of its proper divisors (1422044640).

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

651387840 is a wasteful number, since it uses less digits than its factorization.

651387840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1750 (or 1740 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 42.

The square root of 651387840 is about 25522.3008367192. The cubic root of 651387840 is about 866.8551805570.

The spelling of 651387840 in words is "six hundred fifty-one million, three hundred eighty-seven thousand, eight hundred forty".