51946381 has 2 divisors, whose sum is σ = 51946382. Its totient is φ = 51946380.

The previous prime is 51946379. The next prime is 51946387. The reversal of 51946381 is 18364915.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50282281 + 1664100 = 7091^2 + 1290^2 .

It is a cyclic number.

It is not a de Polignac number, because 51946381 - 2¹ = 51946379 is a prime.

It is a super-2 number, since 2×51946381² = 5396852997994322, which contains 22 as substring.

Together with 51946379, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 51946381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51946387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25973190 + 25973191.

It is an arithmetic number, because the mean of its divisors is an integer number (25973191).

Almost surely, 2^51946381 is an apocalyptic number.

It is an amenable number.

51946381 is a deficient number, since it is larger than the sum of its proper divisors (1).

51946381 is an equidigital number, since it uses as much as digits as its factorization.

51946381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 37.

The square root of 51946381 is about 7207.3837833156. The cubic root of 51946381 is about 373.1227808462.

The spelling of 51946381 in words is "fifty-one million, nine hundred forty-six thousand, three hundred eighty-one".