21046842 has 12 divisors (see below), whose sum is σ = 45601530. Its totient is φ = 7015608.

The previous prime is 21046841. The next prime is 21046847. The reversal of 21046842 is 24864012.

It can be written as a sum of positive squares in only one way, i.e., 20711601 + 335241 = 4551^2 + 579^2 .

It is not an unprimeable number, because it can be changed into a prime (21046841) 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, 584617 + ... + 584652.

Almost surely, 2^21046842 is an apocalyptic number.

21046842 is an abundant number, since it is smaller than the sum of its proper divisors (24554688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21046842 is a wasteful number, since it uses less digits than its factorization.

21046842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1169277 (or 1169274 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 21046842 is about 4587.6837292908. The cubic root of 21046842 is about 276.0973978873.

The spelling of 21046842 in words is "twenty-one million, forty-six thousand, eight hundred forty-two".