21871454 has 16 divisors (see below), whose sum is σ = 35861616. Its totient is φ = 9921600.

The previous prime is 21871453. The next prime is 21871519. The reversal of 21871454 is 45417812.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21871454.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21871453) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20084 + ... + 21144.

It is an arithmetic number, because the mean of its divisors is an integer number (2241351).

Almost surely, 2^21871454 is an apocalyptic number.

21871454 is a deficient number, since it is larger than the sum of its proper divisors (13990162).

21871454 is a wasteful number, since it uses less digits than its factorization.

21871454 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2011.

The product of its digits is 8960, while the sum is 32.

The square root of 21871454 is about 4676.6926347580. The cubic root of 21871454 is about 279.6571228142.

The spelling of 21871454 in words is "twenty-one million, eight hundred seventy-one thousand, four hundred fifty-four".