51801917 has 8 divisors (see below), whose sum is σ = 53668440. Its totient is φ = 49940800.

The previous prime is 51801913. The next prime is 51801929. The reversal of 51801917 is 71910815.

It can be written as a sum of positive squares in 4 ways, for example, as 6791236 + 45010681 = 2606^2 + 6709^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 51801917 - 2² = 51801913 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51801913) 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, 37043 + ... + 38415.

It is an arithmetic number, because the mean of its divisors is an integer number (6708555).

Almost surely, 2^51801917 is an apocalyptic number.

It is an amenable number.

51801917 is a deficient number, since it is larger than the sum of its proper divisors (1866523).

51801917 is a wasteful number, since it uses less digits than its factorization.

51801917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2703.

The product of its (nonzero) digits is 2520, while the sum is 32.

The square root of 51801917 is about 7197.3548613362. The cubic root of 51801917 is about 372.7765722236.

The spelling of 51801917 in words is "fifty-one million, eight hundred one thousand, nine hundred seventeen".