1021305240 has 128 divisors (see below), whose sum is σ = 3439800000. Its totient is φ = 269512704.

The previous prime is 1021305193. The next prime is 1021305247. The reversal of 1021305240 is 425031201.

1021305240 is a `hidden beast` number, since 10 + 2 + 130 + 524 + 0 = 666.

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 (1021305247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 99886 + ... + 109634.

Almost surely, 2^1021305240 is an apocalyptic number.

1021305240 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 1021305240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1719900000).

1021305240 is an abundant number, since it is smaller than the sum of its proper divisors (2418494760).

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

1021305240 is a wasteful number, since it uses less digits than its factorization.

1021305240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9866 (or 9856 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 1021305240 is about 31957.8666371834. The cubic root of 1021305240 is about 1007.0519004711.

Adding to 1021305240 its reverse (425031201), we get a palindrome (1446336441).

The spelling of 1021305240 in words is "one billion, twenty-one million, three hundred five thousand, two hundred forty".