21544541315 has 16 divisors (see below), whose sum is σ = 28359598176. Its totient is φ = 15582182400.

The previous prime is 21544541311. The next prime is 21544541329. The reversal of 21544541315 is 51314544512.

It is a happy number.

It is not a de Polignac number, because 21544541315 - 2² = 21544541311 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21544541311) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1072142 + ... + 1092051.

It is an arithmetic number, because the mean of its divisors is an integer number (1772474886).

Almost surely, 2^21544541315 is an apocalyptic number.

21544541315 is a deficient number, since it is larger than the sum of its proper divisors (6815056861).

21544541315 is a wasteful number, since it uses less digits than its factorization.

21544541315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2164390.

The product of its digits is 48000, while the sum is 35.

The spelling of 21544541315 in words is "twenty-one billion, five hundred forty-four million, five hundred forty-one thousand, three hundred fifteen".