21122515149 has 4 divisors (see below), whose sum is σ = 28163353536. Its totient is φ = 14081676764.

The previous prime is 21122515097. The next prime is 21122515151. The reversal of 21122515149 is 94151522112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21122515149 - 2¹¹ = 21122513101 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122515049) 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, 3520419189 + ... + 3520419194.

It is an arithmetic number, because the mean of its divisors is an integer number (7040838384).

Almost surely, 2^21122515149 is an apocalyptic number.

It is an amenable number.

21122515149 is a deficient number, since it is larger than the sum of its proper divisors (7040838387).

21122515149 is an equidigital number, since it uses as much as digits as its factorization.

21122515149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7040838386.

The product of its digits is 7200, while the sum is 33.

The spelling of 21122515149 in words is "twenty-one billion, one hundred twenty-two million, five hundred fifteen thousand, one hundred forty-nine".