51840990 has 96 divisors (see below), whose sum is σ = 147453696. Its totient is φ = 12579840.

The previous prime is 51840983. The next prime is 51840991. The reversal of 51840990 is 9904815.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51840991) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 46884 + ... + 47976.

It is an arithmetic number, because the mean of its divisors is an integer number (1535976).

Almost surely, 2^51840990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 51840990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73726848).

51840990 is an abundant number, since it is smaller than the sum of its proper divisors (95612706).

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

51840990 is a wasteful number, since it uses less digits than its factorization.

51840990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1154 (or 1151 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 51840990 is about 7200.0687496718. The cubic root of 51840990 is about 372.8702742797.

The spelling of 51840990 in words is "fifty-one million, eight hundred forty thousand, nine hundred ninety".