21115351501 has 16 divisors (see below), whose sum is σ = 22558210560. Its totient is φ = 19720733760.

The previous prime is 21115351487. The next prime is 21115351513. The reversal of 21115351501 is 10515351112.

It is a cyclic number.

It is not a de Polignac number, because 21115351501 - 2⁵ = 21115351469 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115351571) 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, 2875831 + ... + 2883163.

It is an arithmetic number, because the mean of its divisors is an integer number (1409888160).

Almost surely, 2^21115351501 is an apocalyptic number.

It is an amenable number.

21115351501 is a deficient number, since it is larger than the sum of its proper divisors (1442859059).

21115351501 is a wasteful number, since it uses less digits than its factorization.

21115351501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10596.

The product of its (nonzero) digits is 750, while the sum is 25.

The spelling of 21115351501 in words is "twenty-one billion, one hundred fifteen million, three hundred fifty-one thousand, five hundred one".