51619999 has 2 divisors, whose sum is σ = 51620000. Its totient is φ = 51619998.

The previous prime is 51619987. The next prime is 51620011. The reversal of 51619999 is 99991615.

It is a balanced prime because it is at equal distance from previous prime (51619987) and next prime (51620011).

It is a cyclic number.

It is not a de Polignac number, because 51619999 - 2⁹ = 51619487 is a prime.

It is a Chen prime.

51619999 is a modest number, since divided by 9999 gives 5161 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51619499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25809999 + 25810000.

It is an arithmetic number, because the mean of its divisors is an integer number (25810000).

Almost surely, 2^51619999 is an apocalyptic number.

51619999 is a deficient number, since it is larger than the sum of its proper divisors (1).

51619999 is an equidigital number, since it uses as much as digits as its factorization.

51619999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 196830, while the sum is 49.

The square root of 51619999 is about 7184.7059090822. The cubic root of 51619999 is about 372.3396880849.

The spelling of 51619999 in words is "fifty-one million, six hundred nineteen thousand, nine hundred ninety-nine".