21143011431 has 4 divisors (see below), whose sum is σ = 28190681912. Its totient is φ = 14095340952.

The previous prime is 21143011427. The next prime is 21143011433. The reversal of 21143011431 is 13411034112.

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

It is not a de Polignac number, because 21143011431 - 2² = 21143011427 is a prime.

It is a super-2 number, since 2×21143011431² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21143011398 and 21143011407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21143011433) 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, 3523835236 + ... + 3523835241.

It is an arithmetic number, because the mean of its divisors is an integer number (7047670478).

Almost surely, 2^21143011431 is an apocalyptic number.

21143011431 is a deficient number, since it is larger than the sum of its proper divisors (7047670481).

21143011431 is an equidigital number, since it uses as much as digits as its factorization.

21143011431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7047670480.

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 21143011431 its reverse (13411034112), we get a palindrome (34554045543).

The spelling of 21143011431 in words is "twenty-one billion, one hundred forty-three million, eleven thousand, four hundred thirty-one".