1005721200 has 360 divisors, whose sum is σ = 3858837840. Its totient is φ = 240537600.

The previous prime is 1005721187. The next prime is 1005721201. The reversal of 1005721200 is 21275001.

It is a tau number, because it is divible by the number of its divisors (360).

It is a super-2 number, since 2×1005721200² = 2022950264258880000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1005721201) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 4316284 + ... + 4316516.

It is an arithmetic number, because the mean of its divisors is an integer number (10718994).

Almost surely, 2^1005721200 is an apocalyptic number.

1005721200 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 1005721200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1929418920).

1005721200 is an abundant number, since it is smaller than the sum of its proper divisors (2853116640).

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

1005721200 is a wasteful number, since it uses less digits than its factorization.

1005721200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 1005721200 is about 31713.1077001293. The cubic root of 1005721200 is about 1001.9034412792.

Adding to 1005721200 its reverse (21275001), we get a palindrome (1026996201).

The spelling of 1005721200 in words is "one billion, five million, seven hundred twenty-one thousand, two hundred".