21949628 has 6 divisors (see below), whose sum is σ = 38411856. Its totient is φ = 10974812.

The previous prime is 21949559. The next prime is 21949633. The reversal of 21949628 is 82694912.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2743700 + ... + 2743707.

It is an arithmetic number, because the mean of its divisors is an integer number (6401976).

Almost surely, 2^21949628 is an apocalyptic number.

It is an amenable number.

21949628 is a deficient number, since it is larger than the sum of its proper divisors (16462228).

21949628 is a wasteful number, since it uses less digits than its factorization.

21949628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5487411 (or 5487409 counting only the distinct ones).

The product of its digits is 62208, while the sum is 41.

The square root of 21949628 is about 4685.0430094077. The cubic root of 21949628 is about 279.9899146027.

The spelling of 21949628 in words is "twenty-one million, nine hundred forty-nine thousand, six hundred twenty-eight".