19902872481 has 4 divisors (see below), whose sum is σ = 26537163312. Its totient is φ = 13268581652.

The previous prime is 19902872471. The next prime is 19902872489. The reversal of 19902872481 is 18427820991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19902872481 - 2⁵ = 19902872449 is a prime.

It is a super-2 number, since 2×19902872481² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (19902872489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3317145411 + ... + 3317145416.

It is an arithmetic number, because the mean of its divisors is an integer number (6634290828).

Almost surely, 2^19902872481 is an apocalyptic number.

It is an amenable number.

19902872481 is a deficient number, since it is larger than the sum of its proper divisors (6634290831).

19902872481 is an equidigital number, since it uses as much as digits as its factorization.

19902872481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6634290830.

The product of its (nonzero) digits is 580608, while the sum is 51.

The spelling of 19902872481 in words is "nineteen billion, nine hundred two million, eight hundred seventy-two thousand, four hundred eighty-one".