21829742 has 16 divisors (see below), whose sum is σ = 36126000. Its totient is φ = 9810240.

The previous prime is 21829729. The next prime is 21829763. The reversal of 21829742 is 24792812.

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, 3617 + ... + 7532.

It is an arithmetic number, because the mean of its divisors is an integer number (2257875).

Almost surely, 2^21829742 is an apocalyptic number.

21829742 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21829742 is a deficient number, since it is larger than the sum of its proper divisors (14296258).

21829742 is a wasteful number, since it uses less digits than its factorization.

21829742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11251.

The product of its digits is 16128, while the sum is 35.

The square root of 21829742 is about 4672.2309446345. The cubic root of 21829742 is about 279.4792275934.

The spelling of 21829742 in words is "twenty-one million, eight hundred twenty-nine thousand, seven hundred forty-two".