1005579921 has 16 divisors (see below), whose sum is σ = 1417687040. Its totient is φ = 632247120.

The previous prime is 1005579859. The next prime is 1005579923. The reversal of 1005579921 is 1299755001.

It is not a de Polignac number, because 1005579921 - 2¹⁸ = 1005317777 is a prime.

It is a super-2 number, since 2×1005579921² = 2022381955036732482, which contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

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 1005579921.

It is not an unprimeable number, because it can be changed into a prime (1005579923) 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, 26845 + ... + 52266.

It is an arithmetic number, because the mean of its divisors is an integer number (88605440).

Almost surely, 2^1005579921 is an apocalyptic number.

It is an amenable number.

1005579921 is a deficient number, since it is larger than the sum of its proper divisors (412107119).

1005579921 is a wasteful number, since it uses less digits than its factorization.

1005579921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79356.

The product of its (nonzero) digits is 28350, while the sum is 39.

The square root of 1005579921 is about 31710.8801675387. The cubic root of 1005579921 is about 1001.8565248492.

The spelling of 1005579921 in words is "one billion, five million, five hundred seventy-nine thousand, nine hundred twenty-one".