20170236749221 has 24 divisors (see below), whose sum is σ = 21917184236640. Its totient is φ = 18553886035776.

The previous prime is 20170236749197. The next prime is 20170236749287. The reversal of 20170236749221 is 12294763207102.

It is not a de Polignac number, because 20170236749221 - 2¹¹ = 20170236747173 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 (20170236749521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 245521170 + ... + 245603308.

It is an arithmetic number, because the mean of its divisors is an integer number (913216009860).

Almost surely, 2^{20170236749221} is an apocalyptic number.

It is an amenable number.

20170236749221 is a deficient number, since it is larger than the sum of its proper divisors (1746947487419).

20170236749221 is a wasteful number, since it uses less digits than its factorization.

20170236749221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87205 (or 87192 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 46.

The spelling of 20170236749221 in words is "twenty trillion, one hundred seventy billion, two hundred thirty-six million, seven hundred forty-nine thousand, two hundred twenty-one".