51172681 has 8 divisors (see below), whose sum is σ = 61561280. Its totient is φ = 41553648.

The previous prime is 51172679. The next prime is 51172687. The reversal of 51172681 is 18627115.

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 51172681 - 2¹ = 51172679 is a prime.

It is a super-2 number, since 2×51172681² = 5237286561455522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51172687) 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, 192246 + ... + 192511.

It is an arithmetic number, because the mean of its divisors is an integer number (7695160).

Almost surely, 2^51172681 is an apocalyptic number.

It is an amenable number.

51172681 is a deficient number, since it is larger than the sum of its proper divisors (10388599).

51172681 is a wasteful number, since it uses less digits than its factorization.

51172681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384783.

The product of its digits is 3360, while the sum is 31.

The square root of 51172681 is about 7153.5083001280. The cubic root of 51172681 is about 371.2610514155.

Adding to 51172681 its reverse (18627115), we get a palindrome (69799796).

The spelling of 51172681 in words is "fifty-one million, one hundred seventy-two thousand, six hundred eighty-one".