18910995541 has 2 divisors, whose sum is σ = 18910995542. Its totient is φ = 18910995540.

The previous prime is 18910995533. The next prime is 18910995611. The reversal of 18910995541 is 14559901981.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18838660516 + 72335025 = 137254^2 + 8505^2 .

It is a cyclic number.

It is not a de Polignac number, because 18910995541 - 2³ = 18910995533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18910995511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9455497770 + 9455497771.

It is an arithmetic number, because the mean of its divisors is an integer number (9455497771).

Almost surely, 2^18910995541 is an apocalyptic number.

It is an amenable number.

18910995541 is a deficient number, since it is larger than the sum of its proper divisors (1).

18910995541 is an equidigital number, since it uses as much as digits as its factorization.

18910995541 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 583200, while the sum is 52.

The spelling of 18910995541 in words is "eighteen billion, nine hundred ten million, nine hundred ninety-five thousand, five hundred forty-one".