999961511 has 2 divisors, whose sum is σ = 999961512. Its totient is φ = 999961510.

The previous prime is 999961477. The next prime is 999961537. The reversal of 999961511 is 115169999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999961511 - 2¹⁴ = 999945127 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 999961511.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999961541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499980755 + 499980756.

It is an arithmetic number, because the mean of its divisors is an integer number (499980756).

Almost surely, 2^999961511 is an apocalyptic number.

999961511 is a deficient number, since it is larger than the sum of its proper divisors (1).

999961511 is an equidigital number, since it uses as much as digits as its factorization.

999961511 is an evil number, because the sum of its binary digits is even.

The product of its digits is 196830, while the sum is 50.

The square root of 999961511 is about 31622.1680313036. The cubic root of 999961511 is about 999.9871701687.

The spelling of 999961511 in words is "nine hundred ninety-nine million, nine hundred sixty-one thousand, five hundred eleven".