51499999 has 2 divisors, whose sum is σ = 51500000. Its totient is φ = 51499998.

The previous prime is 51499997. The next prime is 51500011. The reversal of 51499999 is 99999415.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51499999 - 2¹ = 51499997 is a prime.

Together with 51499997, it forms a pair of twin primes.

51499999 is a modest number, since divided by 9999 gives 5149 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51499997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25749999 + 25750000.

It is an arithmetic number, because the mean of its divisors is an integer number (25750000).

Almost surely, 2^51499999 is an apocalyptic number.

51499999 is a deficient number, since it is larger than the sum of its proper divisors (1).

51499999 is an equidigital number, since it uses as much as digits as its factorization.

51499999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1180980, while the sum is 55.

The square root of 51499999 is about 7176.3499775304. The cubic root of 51499999 is about 372.0509406287.

The spelling of 51499999 in words is "fifty-one million, four hundred ninety-nine thousand, nine hundred ninety-nine".