51970891 has 4 divisors (see below), whose sum is σ = 59395312. Its totient is φ = 44546472.

The previous prime is 51970889. The next prime is 51970907. The reversal of 51970891 is 19807915.

It is a happy number.

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 51970891 - 2¹ = 51970889 is a prime.

It is a super-2 number, since 2×51970891² = 5401947022667762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51970811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3712200 + ... + 3712213.

It is an arithmetic number, because the mean of its divisors is an integer number (14848828).

Almost surely, 2^51970891 is an apocalyptic number.

51970891 is a deficient number, since it is larger than the sum of its proper divisors (7424421).

51970891 is an equidigital number, since it uses as much as digits as its factorization.

51970891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7424420.

The product of its (nonzero) digits is 22680, while the sum is 40.

The square root of 51970891 is about 7209.0839223857. The cubic root of 51970891 is about 373.1814554592.

The spelling of 51970891 in words is "fifty-one million, nine hundred seventy thousand, eight hundred ninety-one".