51873209 has 8 divisors (see below), whose sum is σ = 53137920. Its totient is φ = 50623056.

The previous prime is 51873203. The next prime is 51873221. The reversal of 51873209 is 90237815.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51873209 - 2⁴ = 51873193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51873203) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3752 + ... + 10854.

It is an arithmetic number, because the mean of its divisors is an integer number (6642240).

Almost surely, 2^51873209 is an apocalyptic number.

It is an amenable number.

51873209 is a deficient number, since it is larger than the sum of its proper divisors (1264711).

51873209 is a wasteful number, since it uses less digits than its factorization.

51873209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7279.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 51873209 is about 7202.3058113357. The cubic root of 51873209 is about 372.9475041542.

The spelling of 51873209 in words is "fifty-one million, eight hundred seventy-three thousand, two hundred nine".