21150344015 has 4 divisors (see below), whose sum is σ = 25380412824. Its totient is φ = 16920275208.

The previous prime is 21150343939. The next prime is 21150344027. The reversal of 21150344015 is 51044305112.

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 21150344015 - 2³⁰ = 20076602191 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2115034397 + ... + 2115034406.

It is an arithmetic number, because the mean of its divisors is an integer number (6345103206).

Almost surely, 2^21150344015 is an apocalyptic number.

21150344015 is a deficient number, since it is larger than the sum of its proper divisors (4230068809).

21150344015 is an equidigital number, since it uses as much as digits as its factorization.

21150344015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4230068808.

The product of its (nonzero) digits is 2400, while the sum is 26.

Adding to 21150344015 its reverse (51044305112), we get a palindrome (72194649127).

The spelling of 21150344015 in words is "twenty-one billion, one hundred fifty million, three hundred forty-four thousand, fifteen".