21139446 has 16 divisors (see below), whose sum is σ = 42334704. Its totient is φ = 7037184.

The previous prime is 21139439. The next prime is 21139453. The reversal of 21139446 is 64493112.

It is an interprime number because it is at equal distance from previous prime (21139439) and next prime (21139453).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3870 + ... + 7566.

It is an arithmetic number, because the mean of its divisors is an integer number (2645919).

Almost surely, 2^21139446 is an apocalyptic number.

21139446 is an abundant number, since it is smaller than the sum of its proper divisors (21195258).

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

21139446 is a wasteful number, since it uses less digits than its factorization.

21139446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4655.

The product of its digits is 5184, while the sum is 30.

The square root of 21139446 is about 4597.7653267647. The cubic root of 21139446 is about 276.5017390920.

The spelling of 21139446 in words is "twenty-one million, one hundred thirty-nine thousand, four hundred forty-six".