21081422 has 8 divisors (see below), whose sum is σ = 31929456. Its totient is φ = 10438272.

The previous prime is 21081413. The next prime is 21081433. The reversal of 21081422 is 22418012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21081394 and 21081403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50963 + ... + 51374.

It is an arithmetic number, because the mean of its divisors is an integer number (3991182).

Almost surely, 2^21081422 is an apocalyptic number.

21081422 is a deficient number, since it is larger than the sum of its proper divisors (10848034).

21081422 is a wasteful number, since it uses less digits than its factorization.

21081422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102442.

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 21081422 is about 4591.4509689204. The cubic root of 21081422 is about 276.2485246606.

Adding to 21081422 its reverse (22418012), we get a palindrome (43499434).

It can be divided in two parts, 2108 and 1422, that multiplied together give a triangular number (2997576 = T₂₄₄₈).

The spelling of 21081422 in words is "twenty-one million, eighty-one thousand, four hundred twenty-two".