20675921399 has 4 divisors (see below), whose sum is σ = 23629624464. Its totient is φ = 17722218336.

The previous prime is 20675921381. The next prime is 20675921401. The reversal of 20675921399 is 99312957602.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20675921399 - 2¹² = 20675917303 is a prime.

It is a super-2 number, since 2×20675921399² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20675921399.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20675921359) by changing a digit.

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, 1476851522 + ... + 1476851535.

It is an arithmetic number, because the mean of its divisors is an integer number (5907406116).

Almost surely, 2^20675921399 is an apocalyptic number.

20675921399 is a deficient number, since it is larger than the sum of its proper divisors (2953703065).

20675921399 is an equidigital number, since it uses as much as digits as its factorization.

20675921399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2953703064.

The product of its (nonzero) digits is 1837080, while the sum is 53.

The spelling of 20675921399 in words is "twenty billion, six hundred seventy-five million, nine hundred twenty-one thousand, three hundred ninety-nine".