51866990 has 48 divisors (see below), whose sum is σ = 109478304. Its totient is φ = 17640000.

The previous prime is 51866981. The next prime is 51867031. The reversal of 51866990 is 9966815.

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, 73640 + ... + 74340.

It is an arithmetic number, because the mean of its divisors is an integer number (2280798).

Almost surely, 2^51866990 is an apocalyptic number.

51866990 is an abundant number, since it is smaller than the sum of its proper divisors (57611314).

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

51866990 is a wasteful number, since it uses less digits than its factorization.

51866990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 873 (or 866 counting only the distinct ones).

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 51866990 is about 7201.8740616592. The cubic root of 51866990 is about 372.9325995225.

The spelling of 51866990 in words is "fifty-one million, eight hundred sixty-six thousand, nine hundred ninety".