20213255690 has 24 divisors (see below), whose sum is σ = 37174496292. Its totient is φ = 7913265920.

The previous prime is 20213255687. The next prime is 20213255701. The reversal of 20213255690 is 9655231202.

It can be written as a sum of positive squares in 2 ways, for example, as 20187010561 + 26245129 = 142081^2 + 5123^2 .

It is a super-2 number, since 2×20213255690² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20213255690.

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 11 ways as a sum of consecutive naturals, for example, 435431 + ... + 479610.

Almost surely, 2^20213255690 is an apocalyptic number.

20213255690 is a deficient number, since it is larger than the sum of its proper divisors (16961240602).

20213255690 is an equidigital number, since it uses as much as digits as its factorization.

20213255690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 915142 (or 915095 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 35.

Adding to 20213255690 its reverse (9655231202), we get a palindrome (29868486892).

The spelling of 20213255690 in words is "twenty billion, two hundred thirteen million, two hundred fifty-five thousand, six hundred ninety".