121121999951 has 2 divisors, whose sum is σ = 121121999952. Its totient is φ = 121121999950.

The previous prime is 121121999917. The next prime is 121122000007. The reversal of 121121999951 is 159999121121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121121999951 - 2¹⁰ = 121121998927 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121121999951.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121121999851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60560999975 + 60560999976.

It is an arithmetic number, because the mean of its divisors is an integer number (60560999976).

Almost surely, 2^121121999951 is an apocalyptic number.

121121999951 is a deficient number, since it is larger than the sum of its proper divisors (1).

121121999951 is an equidigital number, since it uses as much as digits as its factorization.

121121999951 is an evil number, because the sum of its binary digits is even.

The product of its digits is 131220, while the sum is 50.

The spelling of 121121999951 in words is "one hundred twenty-one billion, one hundred twenty-one million, nine hundred ninety-nine thousand, nine hundred fifty-one".