21021020120986 has 8 divisors (see below), whose sum is σ = 31535332392564. Its totient is φ = 10509242656800.

The previous prime is 21021020120977. The next prime is 21021020121047. The reversal of 21021020120986 is 68902102012012.

It can be written as a sum of positive squares in 2 ways, for example, as 20850008924761 + 171011196225 = 4566181^2 + 413535^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21021020120986² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 633681115 + ... + 633714286.

Almost surely, 2^{21021020120986} is an apocalyptic number.

21021020120986 is a deficient number, since it is larger than the sum of its proper divisors (10514312271578).

21021020120986 is a wasteful number, since it uses less digits than its factorization.

21021020120986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1267403696.

The product of its (nonzero) digits is 6912, while the sum is 34.

Adding to 21021020120986 its reverse (68902102012012), we get a palindrome (89923122132998).

The spelling of 21021020120986 in words is "twenty-one trillion, twenty-one billion, twenty million, one hundred twenty thousand, nine hundred eighty-six".