21001293 has 6 divisors (see below), whose sum is σ = 30335214. Its totient is φ = 14000856.

The previous prime is 21001247. The next prime is 21001319. The reversal of 21001293 is 39210012.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 19554084 + 1447209 = 4422^2 + 1203^2 .

It is not a de Polignac number, because 21001293 - 2⁸ = 21001037 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001493) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1166730 + ... + 1166747.

It is an arithmetic number, because the mean of its divisors is an integer number (5055869).

Almost surely, 2^21001293 is an apocalyptic number.

It is an amenable number.

21001293 is a deficient number, since it is larger than the sum of its proper divisors (9333921).

21001293 is a wasteful number, since it uses less digits than its factorization.

21001293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2333483 (or 2333480 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 21001293 is about 4582.7167706504. The cubic root of 21001293 is about 275.8980798853.

The spelling of 21001293 in words is "twenty-one million, one thousand, two hundred ninety-three".