21454555004431 has 4 divisors (see below), whose sum is σ = 21586178041432. Its totient is φ = 21322931967432.

The previous prime is 21454555004359. The next prime is 21454555004437. The reversal of 21454555004431 is 13440055545412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21454555004431 is a prime.

It is a super-2 number, since 2×21454555004431² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21454555004437) 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, 65811518256 + ... + 65811518581.

It is an arithmetic number, because the mean of its divisors is an integer number (5396544510358).

Almost surely, 2^{21454555004431} is an apocalyptic number.

21454555004431 is a deficient number, since it is larger than the sum of its proper divisors (131623037001).

21454555004431 is a wasteful number, since it uses less digits than its factorization.

21454555004431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131623037000.

The product of its (nonzero) digits is 960000, while the sum is 43.

The spelling of 21454555004431 in words is "twenty-one trillion, four hundred fifty-four billion, five hundred fifty-five million, four thousand, four hundred thirty-one".