20403121431 has 16 divisors (see below), whose sum is σ = 33916877568. Its totient is φ = 10599024000.

The previous prime is 20403121429. The next prime is 20403121433. The reversal of 20403121431 is 13412130402.

It is an interprime number because it is at equal distance from previous prime (20403121429) and next prime (20403121433).

It is not a de Polignac number, because 20403121431 - 2¹ = 20403121429 is a prime.

It is a super-2 number, since 2×20403121431² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 20403121398 and 20403121407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20403121433) 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 15 ways as a sum of consecutive naturals, for example, 44162370 + ... + 44162831.

It is an arithmetic number, because the mean of its divisors is an integer number (2119804848).

Almost surely, 2^20403121431 is an apocalyptic number.

20403121431 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20403121431 is a deficient number, since it is larger than the sum of its proper divisors (13513756137).

20403121431 is a wasteful number, since it uses less digits than its factorization.

20403121431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88325222.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 20403121431 its reverse (13412130402), we get a palindrome (33815251833).

The spelling of 20403121431 in words is "twenty billion, four hundred three million, one hundred twenty-one thousand, four hundred thirty-one".