20997550079999 has 16 divisors (see below), whose sum is σ = 21382530612000. Its totient is φ = 20613895441920.

The previous prime is 20997550079963. The next prime is 20997550080037. The reversal of 20997550079999 is 99997005579902.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20997550079999 - 2¹² = 20997550075903 is a prime.

It is a super-2 number, since 2×20997550079999² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (80) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20997550079959) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 247398032 + ... + 247482890.

It is an arithmetic number, because the mean of its divisors is an integer number (1336408163250).

Almost surely, 2^{20997550079999} is an apocalyptic number.

20997550079999 is a deficient number, since it is larger than the sum of its proper divisors (384980532001).

20997550079999 is an equidigital number, since it uses as much as digits as its factorization.

20997550079999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92618.

The product of its (nonzero) digits is 1302030450, while the sum is 80.

The spelling of 20997550079999 in words is "twenty trillion, nine hundred ninety-seven billion, five hundred fifty million, seventy-nine thousand, nine hundred ninety-nine".