20994253648 has 20 divisors (see below), whose sum is σ = 40698281428. Its totient is φ = 10491471360.

The previous prime is 20994253639. The next prime is 20994253663. The reversal of 20994253648 is 84635249902.

It can be written as a sum of positive squares in 2 ways, for example, as 5216883984 + 15777369664 = 72228^2 + 125608^2 .

It is a super-2 number, since 2×20994253648² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20994253595 and 20994253604.

It is a congruent number.

It is an unprimeable number.

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, 322761 + ... + 382312.

Almost surely, 2^20994253648 is an apocalyptic number.

It is an amenable number.

20994253648 is a deficient number, since it is larger than the sum of its proper divisors (19704027780).

20994253648 is a wasteful number, since it uses less digits than its factorization.

20994253648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 706942 (or 706936 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 52.

The spelling of 20994253648 in words is "twenty billion, nine hundred ninety-four million, two hundred fifty-three thousand, six hundred forty-eight".