51615550 has 48 divisors (see below), whose sum is σ = 111019680. Its totient is φ = 17487360.

The previous prime is 51615547. The next prime is 51615569. The reversal of 51615550 is 5551615.

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, 30322 + ... + 31978.

It is an arithmetic number, because the mean of its divisors is an integer number (2312910).

Almost surely, 2^51615550 is an apocalyptic number.

51615550 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

51615550 is an abundant number, since it is smaller than the sum of its proper divisors (59404130).

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

51615550 is a wasteful number, since it uses less digits than its factorization.

51615550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1765 (or 1760 counting only the distinct ones).

The product of its (nonzero) digits is 3750, while the sum is 28.

The square root of 51615550 is about 7184.3962863973. The cubic root of 51615550 is about 372.3289907654.

The spelling of 51615550 in words is "fifty-one million, six hundred fifteen thousand, five hundred fifty".