21851342 has 8 divisors (see below), whose sum is σ = 33834432. Its totient is φ = 10573200.

The previous prime is 21851329. The next prime is 21851351. The reversal of 21851342 is 24315812.

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

It is a super-2 number, since 2×21851342² = 954962294401928, which contains 22 as substring.

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, 176159 + ... + 176282.

It is an arithmetic number, because the mean of its divisors is an integer number (4229304).

Almost surely, 2^21851342 is an apocalyptic number.

21851342 is a deficient number, since it is larger than the sum of its proper divisors (11983090).

21851342 is a wasteful number, since it uses less digits than its factorization.

21851342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352474.

The product of its digits is 1920, while the sum is 26.

The square root of 21851342 is about 4674.5419026895. The cubic root of 21851342 is about 279.5713765117.

The spelling of 21851342 in words is "twenty-one million, eight hundred fifty-one thousand, three hundred forty-two".