51650640 has 120 divisors (see below), whose sum is σ = 181059840. Its totient is φ = 13170432.

The previous prime is 51650633. The next prime is 51650659. The reversal of 51650640 is 4605615.

It is a happy number.

51650640 is a `hidden beast` number, since 5 + 1 + 650 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×51650640² = 5335577224819200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15001 + ... + 18119.

It is an arithmetic number, because the mean of its divisors is an integer number (1508832).

Almost surely, 2^51650640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51650640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90529920).

51650640 is an abundant number, since it is smaller than the sum of its proper divisors (129409200).

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

51650640 is a wasteful number, since it uses less digits than its factorization.

51650640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3161 (or 3152 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 51650640 is about 7186.8379695107. The cubic root of 51650640 is about 372.4133456075.

The spelling of 51650640 in words is "fifty-one million, six hundred fifty thousand, six hundred forty".