19901619461 has 2 divisors, whose sum is σ = 19901619462. Its totient is φ = 19901619460.

The previous prime is 19901619371. The next prime is 19901619481. The reversal of 19901619461 is 16491610991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16232288836 + 3669330625 = 127406^2 + 60575^2 .

It is a cyclic number.

It is not a de Polignac number, because 19901619461 - 2¹⁰ = 19901618437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19901619481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9950809730 + 9950809731.

It is an arithmetic number, because the mean of its divisors is an integer number (9950809731).

Almost surely, 2^19901619461 is an apocalyptic number.

It is an amenable number.

19901619461 is a deficient number, since it is larger than the sum of its proper divisors (1).

19901619461 is an equidigital number, since it uses as much as digits as its factorization.

19901619461 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 104976, while the sum is 47.

The spelling of 19901619461 in words is "nineteen billion, nine hundred one million, six hundred nineteen thousand, four hundred sixty-one".