21037642 has 8 divisors (see below), whose sum is σ = 31911300. Its totient is φ = 10400544.

The previous prime is 21037631. The next prime is 21037649. The reversal of 21037642 is 24673012.

It can be written as a sum of positive squares in 2 ways, for example, as 20711601 + 326041 = 4551^2 + 571^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21037649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58917 + ... + 59272.

Almost surely, 2^21037642 is an apocalyptic number.

21037642 is a deficient number, since it is larger than the sum of its proper divisors (10873658).

21037642 is a wasteful number, since it uses less digits than its factorization.

21037642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118280.

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 21037642 is about 4586.6809350553. The cubic root of 21037642 is about 276.0571627733.

The spelling of 21037642 in words is "twenty-one million, thirty-seven thousand, six hundred forty-two".