99999999551 has 2 divisors, whose sum is σ = 99999999552. Its totient is φ = 99999999550.

The previous prime is 99999999529. The next prime is 99999999557. The reversal of 99999999551 is 15599999999.

It is a strong prime.

It is an emirp because it is prime and its reverse (15599999999) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99999999551 is a prime.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 99999999551.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99999999557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49999999775 + 49999999776.

It is an arithmetic number, because the mean of its divisors is an integer number (49999999776).

Almost surely, 2^99999999551 is an apocalyptic number.

99999999551 is a deficient number, since it is larger than the sum of its proper divisors (1).

99999999551 is an equidigital number, since it uses as much as digits as its factorization.

99999999551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1076168025, while the sum is 83.

The spelling of 99999999551 in words is "ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, five hundred fifty-one".