21113746 has 4 divisors (see below), whose sum is σ = 31670622. Its totient is φ = 10556872.

The previous prime is 21113723. The next prime is 21113773. The reversal of 21113746 is 64731112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 20602521 + 511225 = 4539^2 + 715^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21113746.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5278435 + ... + 5278438.

Almost surely, 2^21113746 is an apocalyptic number.

21113746 is a deficient number, since it is larger than the sum of its proper divisors (10556876).

21113746 is a wasteful number, since it uses less digits than its factorization.

21113746 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10556875.

The product of its digits is 1008, while the sum is 25.

The square root of 21113746 is about 4594.9696408137. The cubic root of 21113746 is about 276.3896425506.

Adding to 21113746 its reverse (64731112), we get a palindrome (85844858).

The spelling of 21113746 in words is "twenty-one million, one hundred thirteen thousand, seven hundred forty-six".