21767130 has 160 divisors (see below), whose sum is σ = 73180800. Its totient is φ = 4510080.

The previous prime is 21767099. The next prime is 21767147. The reversal of 21767130 is 3176712.

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

It is a junction number, because it is equal to n+sod(n) for n = 21767094 and 21767103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 62196 + ... + 62544.

It is an arithmetic number, because the mean of its divisors is an integer number (457380).

Almost surely, 2^21767130 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21767130, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36590400).

21767130 is an abundant number, since it is smaller than the sum of its proper divisors (51413670).

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

21767130 is a wasteful number, since it uses less digits than its factorization.

21767130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 1764, while the sum is 27.

The square root of 21767130 is about 4665.5256938527. The cubic root of 21767130 is about 279.2117712325.

The spelling of 21767130 in words is "twenty-one million, seven hundred sixty-seven thousand, one hundred thirty".