19902913 has 2 divisors, whose sum is σ = 19902914. Its totient is φ = 19902912.

The previous prime is 19902901. The next prime is 19902947. The reversal of 19902913 is 31920991.

It is an a-pointer prime, because the next prime (19902947) can be obtained adding 19902913 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19210689 + 692224 = 4383^2 + 832^2 .

It is a cyclic number.

It is not a de Polignac number, because 19902913 - 2⁵ = 19902881 is a prime.

It is a super-2 number, since 2×19902913² = 792251891771138, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19902983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9951456 + 9951457.

It is an arithmetic number, because the mean of its divisors is an integer number (9951457).

Almost surely, 2^19902913 is an apocalyptic number.

It is an amenable number.

19902913 is a deficient number, since it is larger than the sum of its proper divisors (1).

19902913 is an equidigital number, since it uses as much as digits as its factorization.

19902913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4374, while the sum is 34.

The square root of 19902913 is about 4461.2680932668. The cubic root of 19902913 is about 271.0018245816.

The spelling of 19902913 in words is "nineteen million, nine hundred two thousand, nine hundred thirteen".