1902919142821 has 2 divisors, whose sum is σ = 1902919142822. Its totient is φ = 1902919142820.

The previous prime is 1902919142809. The next prime is 1902919142867. The reversal of 1902919142821 is 1282419192091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1852282892196 + 50636250625 = 1360986^2 + 225025^2 .

It is a cyclic number.

It is not a de Polignac number, because 1902919142821 - 2³⁷ = 1765480189349 is a prime.

It is a super-2 number, since 2×1902919142821² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1902919142921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 951459571410 + 951459571411.

It is an arithmetic number, because the mean of its divisors is an integer number (951459571411).

Almost surely, 2^{1902919142821} is an apocalyptic number.

It is an amenable number.

1902919142821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1902919142821 is an equidigital number, since it uses as much as digits as its factorization.

1902919142821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 186624, while the sum is 49.

The spelling of 1902919142821 in words is "one trillion, nine hundred two billion, nine hundred nineteen million, one hundred forty-two thousand, eight hundred twenty-one".