21772650 has 48 divisors (see below), whose sum is σ = 55469664. Its totient is φ = 5647680.

The previous prime is 21772607. The next prime is 21772691. The reversal of 21772650 is 5627712.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon 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, 3589 + ... + 7511.

It is an arithmetic number, because the mean of its divisors is an integer number (1155618).

Almost surely, 2^21772650 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21772650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27734832).

21772650 is an abundant number, since it is smaller than the sum of its proper divisors (33697014).

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

21772650 is a wasteful number, since it uses less digits than its factorization.

21772650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3975 (or 3970 counting only the distinct ones).

The product of its (nonzero) digits is 5880, while the sum is 30.

The square root of 21772650 is about 4666.1172295604. The cubic root of 21772650 is about 279.2353713229.

It can be divided in two parts, 21772 and 650, that added together give a palindrome (22422).

The spelling of 21772650 in words is "twenty-one million, seven hundred seventy-two thousand, six hundred fifty".