21901433 has 4 divisors (see below), whose sum is σ = 23054160. Its totient is φ = 20748708.

The previous prime is 21901427. The next prime is 21901463. The reversal of 21901433 is 33410912.

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 21901433 - 2²⁰ = 20852857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21901399 and 21901408.

It is not an unprimeable number, because it can be changed into a prime (21901403) 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, 576335 + ... + 576372.

It is an arithmetic number, because the mean of its divisors is an integer number (5763540).

Almost surely, 2^21901433 is an apocalyptic number.

It is an amenable number.

21901433 is a deficient number, since it is larger than the sum of its proper divisors (1152727).

21901433 is a wasteful number, since it uses less digits than its factorization.

21901433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1152726.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 21901433 is about 4679.8966868938. The cubic root of 21901433 is about 279.7848389574.

The spelling of 21901433 in words is "twenty-one million, nine hundred one thousand, four hundred thirty-three".