1009902416821 has 2 divisors, whose sum is σ = 1009902416822. Its totient is φ = 1009902416820.

The previous prime is 1009902416759. The next prime is 1009902416833. The reversal of 1009902416821 is 1286142099001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 987859075921 + 22043340900 = 993911^2 + 148470^2 .

It is a cyclic number.

It is not a de Polignac number, because 1009902416821 - 2³⁹ = 460146602933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1009902416881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 504951208410 + 504951208411.

It is an arithmetic number, because the mean of its divisors is an integer number (504951208411).

Almost surely, 2^{1009902416821} is an apocalyptic number.

It is an amenable number.

1009902416821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1009902416821 is an equidigital number, since it uses as much as digits as its factorization.

1009902416821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 62208, while the sum is 43.

The spelling of 1009902416821 in words is "one trillion, nine billion, nine hundred two million, four hundred sixteen thousand, eight hundred twenty-one".