221021010 has 96 divisors (see below), whose sum is σ = 677993472. Its totient is φ = 48885120.

The previous prime is 221020957. The next prime is 221021033. The reversal of 221021010 is 10120122.

It is a super-2 number, since 2×221021010² = 97700573722840200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 221020983 and 221021001.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13872 + ... + 25188.

It is an arithmetic number, because the mean of its divisors is an integer number (7062432).

Almost surely, 2^221021010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221021010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338996736).

221021010 is an abundant number, since it is smaller than the sum of its proper divisors (456972462).

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

221021010 is a wasteful number, since it uses less digits than its factorization.

221021010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11368 (or 11365 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 221021010 is about 14866.7753732946. The cubic root of 221021010 is about 604.6135181608.

Adding to 221021010 its reverse (10120122), we get a palindrome (231141132).

It can be divided in two parts, 2210 and 21010, that added together give a triangular number (23220 = T₂₁₅).

The spelling of 221021010 in words is "two hundred twenty-one million, twenty-one thousand, ten".