1005055021 has 8 divisors (see below), whose sum is σ = 1021470840. Its totient is φ = 988710912.

The previous prime is 1005054949. The next prime is 1005055033. The reversal of 1005055021 is 1205505001.

It can be written as a sum of positive squares in 4 ways, for example, as 361418121 + 643636900 = 19011^2 + 25370^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1005055021 - 2²¹ = 1002957869 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1005055021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1005055321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10701 + ... + 46093.

It is an arithmetic number, because the mean of its divisors is an integer number (127683855).

Almost surely, 2^1005055021 is an apocalyptic number.

It is an amenable number.

1005055021 is a deficient number, since it is larger than the sum of its proper divisors (16415819).

1005055021 is an equidigital number, since it uses as much as digits as its factorization.

1005055021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35855.

The product of its (nonzero) digits is 250, while the sum is 19.

The square root of 1005055021 is about 31702.6027480395. The cubic root of 1005055021 is about 1001.6821756982.

The spelling of 1005055021 in words is "one billion, five million, fifty-five thousand, twenty-one".