21953322549 has 24 divisors (see below), whose sum is σ = 32324429592. Its totient is φ = 14352399360.

The previous prime is 21953322541. The next prime is 21953322553. The reversal of 21953322549 is 94522335912.

21953322549 is a `hidden beast` number, since 21 + 9 + 53 + 32 + 2 + 549 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 8211621924 + 13741700625 = 90618^2 + 117225^2 .

It is not a de Polignac number, because 21953322549 - 2³ = 21953322541 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21953322541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1077949 + ... + 1098125.

It is an arithmetic number, because the mean of its divisors is an integer number (1346851233).

Almost surely, 2^21953322549 is an apocalyptic number.

It is an amenable number.

21953322549 is a deficient number, since it is larger than the sum of its proper divisors (10371107043).

21953322549 is a wasteful number, since it uses less digits than its factorization.

21953322549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22517 (or 22514 counting only the distinct ones).

The product of its digits is 583200, while the sum is 45.

The spelling of 21953322549 in words is "twenty-one billion, nine hundred fifty-three million, three hundred twenty-two thousand, five hundred forty-nine".