20400123002 has 16 divisors (see below), whose sum is σ = 34974755520. Its totient is φ = 8742130848.

The previous prime is 20400123001. The next prime is 20400123011. The reversal of 20400123002 is 20032100402.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (20400123001) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115013 + ... + 232439.

It is an arithmetic number, because the mean of its divisors is an integer number (2185922220).

Almost surely, 2^20400123002 is an apocalyptic number.

20400123002 is a deficient number, since it is larger than the sum of its proper divisors (14574632518).

20400123002 is a wasteful number, since it uses less digits than its factorization.

20400123002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129845.

The product of its (nonzero) digits is 96, while the sum is 14.

Adding to 20400123002 its reverse (20032100402), we get a palindrome (40432223404).

The spelling of 20400123002 in words is "twenty billion, four hundred million, one hundred twenty-three thousand, two".