21492148849 has 16 divisors (see below), whose sum is σ = 22643082000. Its totient is φ = 20369905920.

The previous prime is 21492148829. The next prime is 21492148859. The reversal of 21492148849 is 94884129412.

It can be written as a sum of positive squares in 8 ways, for example, as 19642624 + 21472506225 = 4432^2 + 146535^2 .

It is a cyclic number.

It is not a de Polignac number, because 21492148849 - 2²³ = 21483760241 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21492148796 and 21492148805.

It is not an unprimeable number, because it can be changed into a prime (21492148829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 888487 + ... + 912355.

It is an arithmetic number, because the mean of its divisors is an integer number (1415192625).

Almost surely, 2^21492148849 is an apocalyptic number.

21492148849 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21492148849 is a deficient number, since it is larger than the sum of its proper divisors (1150933151).

21492148849 is a wasteful number, since it uses less digits than its factorization.

21492148849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24468.

The product of its digits is 1327104, while the sum is 52.

The spelling of 21492148849 in words is "twenty-one billion, four hundred ninety-two million, one hundred forty-eight thousand, eight hundred forty-nine".