21534113431 has 8 divisors (see below), whose sum is σ = 21995153424. Its totient is φ = 21075100800.

The previous prime is 21534113417. The next prime is 21534113437. The reversal of 21534113431 is 13431143512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21534113431 - 2¹⁷ = 21533982359 is a prime.

It is a super-2 number, since 2×21534113431² (a number of 21 digits) contains 22 as substring.

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 21534113431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21534113437) 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 7 ways as a sum of consecutive naturals, for example, 485361 + ... + 527866.

It is an arithmetic number, because the mean of its divisors is an integer number (2749394178).

Almost surely, 2^21534113431 is an apocalyptic number.

21534113431 is a deficient number, since it is larger than the sum of its proper divisors (461039993).

21534113431 is a wasteful number, since it uses less digits than its factorization.

21534113431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1013681.

The product of its digits is 4320, while the sum is 28.

Adding to 21534113431 its reverse (13431143512), we get a palindrome (34965256943).

The spelling of 21534113431 in words is "twenty-one billion, five hundred thirty-four million, one hundred thirteen thousand, four hundred thirty-one".