51990319 has 4 divisors (see below), whose sum is σ = 53096544. Its totient is φ = 50884096.

The previous prime is 51990307. The next prime is 51990343. The reversal of 51990319 is 91309915.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51990319 - 2¹⁵ = 51957551 is a prime.

It is a super-2 number, since 2×51990319² = 5405986539443522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51990119) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 553042 + ... + 553135.

It is an arithmetic number, because the mean of its divisors is an integer number (13274136).

Almost surely, 2^51990319 is an apocalyptic number.

51990319 is a deficient number, since it is larger than the sum of its proper divisors (1106225).

51990319 is a wasteful number, since it uses less digits than its factorization.

51990319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1106224.

The product of its (nonzero) digits is 10935, while the sum is 37.

The square root of 51990319 is about 7210.4312631076. The cubic root of 51990319 is about 373.2279511412.

The spelling of 51990319 in words is "fifty-one million, nine hundred ninety thousand, three hundred nineteen".