1021021000 has 64 divisors (see below), whose sum is σ = 2402814960. Its totient is φ = 406080000.

The previous prime is 1021020961. The next prime is 1021021007. The reversal of 1021021000 is 1201201.

It can be written as a sum of positive squares in 8 ways, for example, as 32421636 + 988599364 = 5694^2 + 31442^2 .

It is not an unprimeable number, because it can be changed into a prime (1021021007) 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, 178180 + ... + 183820.

Almost surely, 2^1021021000 is an apocalyptic number.

1021021000 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 1021021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1201407480).

1021021000 is an abundant number, since it is smaller than the sum of its proper divisors (1381793960).

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

1021021000 is a wasteful number, since it uses less digits than its factorization.

1021021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5843 (or 5829 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

The square root of 1021021000 is about 31953.4192223618. The cubic root of 1021021000 is about 1006.9584674209.

Adding to 1021021000 its reverse (1201201), we get a palindrome (1022222201).

The spelling of 1021021000 in words is "one billion, twenty-one million, twenty-one thousand".