21497000544 has 72 divisors (see below), whose sum is σ = 61198661160. Its totient is φ = 7157864448.

The previous prime is 21497000527. The next prime is 21497000563. The reversal of 21497000544 is 44500079412.

It is a happy number.

21497000544 is a `hidden beast` number, since 2 + 1 + 49 + 70 + 0 + 0 + 544 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21497000499 and 21497000508.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 227379 + ... + 307725.

It is an arithmetic number, because the mean of its divisors is an integer number (849981405).

Almost surely, 2^21497000544 is an apocalyptic number.

21497000544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21497000544 is an abundant number, since it is smaller than the sum of its proper divisors (39701660616).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21497000544 is a wasteful number, since it uses less digits than its factorization.

21497000544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81292 (or 81281 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

Adding to 21497000544 its reverse (44500079412), we get a palindrome (65997079956).

The spelling of 21497000544 in words is "twenty-one billion, four hundred ninety-seven million, five hundred forty-four", and thus it is an aban number.