21001501235 has 32 divisors (see below), whose sum is σ = 29630748672. Its totient is φ = 14087940480.

The previous prime is 21001501229. The next prime is 21001501237. The reversal of 21001501235 is 53210510012.

It is a happy number.

It is not a de Polignac number, because 21001501235 - 2⁴ = 21001501219 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21001501237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 966662 + ... + 988148.

It is an arithmetic number, because the mean of its divisors is an integer number (925960896).

Almost surely, 2^21001501235 is an apocalyptic number.

21001501235 is a deficient number, since it is larger than the sum of its proper divisors (8629247437).

21001501235 is a wasteful number, since it uses less digits than its factorization.

21001501235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22883.

The product of its (nonzero) digits is 300, while the sum is 20.

The spelling of 21001501235 in words is "twenty-one billion, one million, five hundred one thousand, two hundred thirty-five".