51201919 has 2 divisors, whose sum is σ = 51201920. Its totient is φ = 51201918.

The previous prime is 51201889. The next prime is 51201923. The reversal of 51201919 is 91910215.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51201919 - 2⁹ = 51201407 is a prime.

It is a super-2 number, since 2×51201919² = 5243273018565122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51201959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25600959 + 25600960.

It is an arithmetic number, because the mean of its divisors is an integer number (25600960).

Almost surely, 2^51201919 is an apocalyptic number.

51201919 is a deficient number, since it is larger than the sum of its proper divisors (1).

51201919 is an equidigital number, since it uses as much as digits as its factorization.

51201919 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 810, while the sum is 28.

The square root of 51201919 is about 7155.5516209444. The cubic root of 51201919 is about 371.3317458024.

The spelling of 51201919 in words is "fifty-one million, two hundred one thousand, nine hundred nineteen".