21531000454115 has 4 divisors (see below), whose sum is σ = 25837200544944. Its totient is φ = 17224800363288.

The previous prime is 21531000454081. The next prime is 21531000454163. The reversal of 21531000454115 is 51145400013512.

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

It is a cyclic number.

It is not a de Polignac number, because 21531000454115 - 2²² = 21530996259811 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2153100045407 + ... + 2153100045416.

It is an arithmetic number, because the mean of its divisors is an integer number (6459300136236).

Almost surely, 2^{21531000454115} is an apocalyptic number.

21531000454115 is a deficient number, since it is larger than the sum of its proper divisors (4306200090829).

21531000454115 is an equidigital number, since it uses as much as digits as its factorization.

21531000454115 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4306200090828.

The product of its (nonzero) digits is 12000, while the sum is 32.

Adding to 21531000454115 its reverse (51145400013512), we get a palindrome (72676400467627).

The spelling of 21531000454115 in words is "twenty-one trillion, five hundred thirty-one billion, four hundred fifty-four thousand, one hundred fifteen".