21168742 has 16 divisors (see below), whose sum is σ = 36613152. Its totient is φ = 8991360.

The previous prime is 21168713. The next prime is 21168767. The reversal of 21168742 is 24786112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5109 + ... + 8272.

It is an arithmetic number, because the mean of its divisors is an integer number (2288322).

Almost surely, 2^21168742 is an apocalyptic number.

21168742 is a deficient number, since it is larger than the sum of its proper divisors (15444410).

21168742 is a wasteful number, since it uses less digits than its factorization.

21168742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13503.

The product of its digits is 5376, while the sum is 31.

The square root of 21168742 is about 4600.9501192688. The cubic root of 21168742 is about 276.6294096699.

The spelling of 21168742 in words is "twenty-one million, one hundred sixty-eight thousand, seven hundred forty-two".