20399329123 has 2 divisors, whose sum is σ = 20399329124. Its totient is φ = 20399329122.

The previous prime is 20399329099. The next prime is 20399329127. The reversal of 20399329123 is 32192399302.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20399329123 is a prime.

It is a super-2 number, since 2×20399329123² (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 20399329123.

It is not a weakly prime, because it can be changed into another prime (20399329127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10199664561 + 10199664562.

It is an arithmetic number, because the mean of its divisors is an integer number (10199664562).

Almost surely, 2^20399329123 is an apocalyptic number.

20399329123 is a deficient number, since it is larger than the sum of its proper divisors (1).

20399329123 is an equidigital number, since it uses as much as digits as its factorization.

20399329123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 157464, while the sum is 43.

The spelling of 20399329123 in words is "twenty billion, three hundred ninety-nine million, three hundred twenty-nine thousand, one hundred twenty-three".