21755722 has 8 divisors (see below), whose sum is σ = 34351200. Its totient is φ = 10305324.

The previous prime is 21755717. The next prime is 21755761. The reversal of 21755722 is 22755712.

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

It is a super-2 number, since 2×21755722² = 946622879482568, which contains 22 as substring.

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, 286222 + ... + 286297.

It is an arithmetic number, because the mean of its divisors is an integer number (4293900).

Almost surely, 2^21755722 is an apocalyptic number.

21755722 is a deficient number, since it is larger than the sum of its proper divisors (12595478).

21755722 is a wasteful number, since it uses less digits than its factorization.

21755722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 572540.

The product of its digits is 9800, while the sum is 31.

The square root of 21755722 is about 4664.3029489946. The cubic root of 21755722 is about 279.1629850657.

The spelling of 21755722 in words is "twenty-one million, seven hundred fifty-five thousand, seven hundred twenty-two".