21954766 has 8 divisors (see below), whose sum is σ = 34665480. Its totient is φ = 10399608.

The previous prime is 21954763. The next prime is 21954767. The reversal of 21954766 is 66745912.

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

It is a super-2 number, since 2×21954766² = 964023500229512, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21954763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 288841 + ... + 288916.

It is an arithmetic number, because the mean of its divisors is an integer number (4333185).

Almost surely, 2^21954766 is an apocalyptic number.

21954766 is a deficient number, since it is larger than the sum of its proper divisors (12710714).

21954766 is a wasteful number, since it uses less digits than its factorization.

21954766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577778.

The product of its digits is 90720, while the sum is 40.

The square root of 21954766 is about 4685.5913180729. The cubic root of 21954766 is about 280.0117597102.

The spelling of 21954766 in words is "twenty-one million, nine hundred fifty-four thousand, seven hundred sixty-six".