19277999921 has 2 divisors, whose sum is σ = 19277999922. Its totient is φ = 19277999920.

The previous prime is 19277999911. The next prime is 19278000023. The reversal of 19277999921 is 12999977291.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14722424896 + 4555575025 = 121336^2 + 67495^2 .

It is a cyclic number.

It is not a de Polignac number, because 19277999921 - 2⁶ = 19277999857 is a prime.

It is not a weakly prime, because it can be changed into another prime (19277999911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9638999960 + 9638999961.

It is an arithmetic number, because the mean of its divisors is an integer number (9638999961).

Almost surely, 2^19277999921 is an apocalyptic number.

It is an amenable number.

19277999921 is a deficient number, since it is larger than the sum of its proper divisors (1).

19277999921 is an equidigital number, since it uses as much as digits as its factorization.

19277999921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11573604, while the sum is 65.

The spelling of 19277999921 in words is "nineteen billion, two hundred seventy-seven million, nine hundred ninety-nine thousand, nine hundred twenty-one".