21611742 has 8 divisors (see below), whose sum is σ = 43223496. Its totient is φ = 7203912.

The previous prime is 21611731. The next prime is 21611767. The reversal of 21611742 is 24711612.

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

21611742 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1800973 + ... + 1800984.

It is an arithmetic number, because the mean of its divisors is an integer number (5402937).

Almost surely, 2^21611742 is an apocalyptic number.

21611742 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21611742 is a wasteful number, since it uses less digits than its factorization.

21611742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3601962.

The product of its digits is 672, while the sum is 24.

The square root of 21611742 is about 4648.8430818861. The cubic root of 21611742 is about 278.5457852605.

The spelling of 21611742 in words is "twenty-one million, six hundred eleven thousand, seven hundred forty-two".