51219631 has 2 divisors, whose sum is σ = 51219632. Its totient is φ = 51219630.

The previous prime is 51219601. The next prime is 51219659. The reversal of 51219631 is 13691215.

It is an a-pointer prime, because the next prime (51219659) can be obtained adding 51219631 to its sum of digits (28).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51219631 - 2¹³ = 51211439 is a prime.

It is a super-2 number, since 2×51219631² = 5246901199552322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 51219631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51219601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25609815 + 25609816.

It is an arithmetic number, because the mean of its divisors is an integer number (25609816).

Almost surely, 2^51219631 is an apocalyptic number.

51219631 is a deficient number, since it is larger than the sum of its proper divisors (1).

51219631 is an equidigital number, since it uses as much as digits as its factorization.

51219631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1620, while the sum is 28.

The square root of 51219631 is about 7156.7891543625. The cubic root of 51219631 is about 371.3745584532.

The spelling of 51219631 in words is "fifty-one million, two hundred nineteen thousand, six hundred thirty-one".