21755126 has 4 divisors (see below), whose sum is σ = 32632692. Its totient is φ = 10877562.

The previous prime is 21755113. The next prime is 21755137. The reversal of 21755126 is 62155712.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

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, 5438780 + ... + 5438783.

It is an arithmetic number, because the mean of its divisors is an integer number (8158173).

Almost surely, 2^21755126 is an apocalyptic number.

21755126 is a deficient number, since it is larger than the sum of its proper divisors (10877566).

21755126 is a wasteful number, since it uses less digits than its factorization.

21755126 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10877565.

The product of its digits is 4200, while the sum is 29.

The square root of 21755126 is about 4664.2390590535. The cubic root of 21755126 is about 279.1604358105.

The spelling of 21755126 in words is "twenty-one million, seven hundred fifty-five thousand, one hundred twenty-six".