21761136 has 120 divisors (see below), whose sum is σ = 65672880. Its totient is φ = 6967296.

The previous prime is 21761093. The next prime is 21761153. The reversal of 21761136 is 63116712.

21761136 is a `hidden beast` number, since 2 + 17 + 611 + 36 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 112656 + ... + 112848.

It is an arithmetic number, because the mean of its divisors is an integer number (547274).

Almost surely, 2^21761136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21761136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32836440).

21761136 is an abundant number, since it is smaller than the sum of its proper divisors (43911744).

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

21761136 is a wasteful number, since it uses less digits than its factorization.

21761136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245 (or 227 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 21761136 is about 4664.8832782825. The cubic root of 21761136 is about 279.1861400935.

Adding to 21761136 its reverse (63116712), we get a palindrome (84877848).

The spelling of 21761136 in words is "twenty-one million, seven hundred sixty-one thousand, one hundred thirty-six".