1205021000 has 64 divisors (see below), whose sum is σ = 2833608960. Its totient is φ = 479640000.

The previous prime is 1205020987. The next prime is 1205021003. The reversal of 1205021000 is 1205021.

It is a super-2 number, since 2×1205021000² = 2904151220882000000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1205021003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 208145 + ... + 213855.

It is an arithmetic number, because the mean of its divisors is an integer number (44275140).

Almost surely, 2^1205021000 is an apocalyptic number.

1205021000 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 1205021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1416804480).

1205021000 is an abundant number, since it is smaller than the sum of its proper divisors (1628587960).

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

1205021000 is a wasteful number, since it uses less digits than its factorization.

1205021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5943 (or 5929 counting only the distinct ones).

The product of its (nonzero) digits is 20, while the sum is 11.

The square root of 1205021000 is about 34713.4123934827. The cubic root of 1205021000 is about 1064.1386203588.

Adding to 1205021000 its reverse (1205021), we get a palindrome (1206226021).

1205021000 divided by its reverse (1205021) gives a cube (1000 = 10³).

The spelling of 1205021000 in words is "one billion, two hundred five million, twenty-one thousand".