21649052439 has 64 divisors (see below), whose sum is σ = 38048993280. Its totient is φ = 11908892160.

The previous prime is 21649052437. The next prime is 21649052449. The reversal of 21649052439 is 93425094612.

21649052439 is a `hidden beast` number, since 2 + 1 + 6 + 4 + 90 + 524 + 39 = 666.

It is not a de Polignac number, because 21649052439 - 2¹ = 21649052437 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21649052394 and 21649052403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21649052437) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 521887 + ... + 561839.

It is an arithmetic number, because the mean of its divisors is an integer number (594515520).

Almost surely, 2^21649052439 is an apocalyptic number.

21649052439 is a deficient number, since it is larger than the sum of its proper divisors (16399940841).

21649052439 is a wasteful number, since it uses less digits than its factorization.

21649052439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40077 (or 40071 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The spelling of 21649052439 in words is "twenty-one billion, six hundred forty-nine million, fifty-two thousand, four hundred thirty-nine".