51686261 has 8 divisors (see below), whose sum is σ = 56591904. Its totient is φ = 46815120.

The previous prime is 51686227. The next prime is 51686287. The reversal of 51686261 is 16268615.

It is a happy number.

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

It is not a de Polignac number, because 51686261 - 2⁶ = 51686197 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 (51686291) 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, 5435 + ... + 11528.

It is an arithmetic number, because the mean of its divisors is an integer number (7073988).

Almost surely, 2^51686261 is an apocalyptic number.

It is an amenable number.

51686261 is a deficient number, since it is larger than the sum of its proper divisors (4905643).

51686261 is a wasteful number, since it uses less digits than its factorization.

51686261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17251.

The product of its digits is 17280, while the sum is 35.

The square root of 51686261 is about 7189.3157532550. The cubic root of 51686261 is about 372.4989378827.

The spelling of 51686261 in words is "fifty-one million, six hundred eighty-six thousand, two hundred sixty-one".