105721000 has 128 divisors (see below), whose sum is σ = 308655360. Its totient is φ = 32928000.

The previous prime is 105720973. The next prime is 105721019. The reversal of 105721000 is 127501.

It is a super-2 number, since 2×105721000² = 22353859682000000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 76314 + ... + 77686.

It is an arithmetic number, because the mean of its divisors is an integer number (2411370).

Almost surely, 2^105721000 is an apocalyptic number.

105721000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 105721000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154327680).

105721000 is an abundant number, since it is smaller than the sum of its proper divisors (202934360).

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

105721000 is a wasteful number, since it uses less digits than its factorization.

105721000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1412 (or 1398 counting only the distinct ones).

The product of its (nonzero) digits is 70, while the sum is 16.

The square root of 105721000 is about 10282.0717756686. The cubic root of 105721000 is about 472.8467635450.

Adding to 105721000 its reverse (127501), we get a palindrome (105848501).

The spelling of 105721000 in words is "one hundred five million, seven hundred twenty-one thousand".