20403004121 has 4 divisors (see below), whose sum is σ = 21603180852. Its totient is φ = 19202827392.

The previous prime is 20403004109. The next prime is 20403004147. The reversal of 20403004121 is 12140030402.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14868388096 + 5534616025 = 121936^2 + 74395^2 .

It is a cyclic number.

It is not a de Polignac number, because 20403004121 - 2⁶ = 20403004057 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17), and also a Moran number because the ratio is a prime number: 1200176713 = 20403004121 / (2 + 0 + 4 + 0 + 3 + 0 + 0 + 4 + 1 + 2 + 1).

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 20403004121.

It is not an unprimeable number, because it can be changed into a prime (20403304121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 600088340 + ... + 600088373.

It is an arithmetic number, because the mean of its divisors is an integer number (5400795213).

Almost surely, 2^20403004121 is an apocalyptic number.

It is an amenable number.

20403004121 is a deficient number, since it is larger than the sum of its proper divisors (1200176731).

20403004121 is a wasteful number, since it uses less digits than its factorization.

20403004121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1200176730.

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 20403004121 its reverse (12140030402), we get a palindrome (32543034523).

The spelling of 20403004121 in words is "twenty billion, four hundred three million, four thousand, one hundred twenty-one".