1021490865 has 16 divisors (see below), whose sum is σ = 1815984000. Its totient is φ = 544795056.

The previous prime is 1021490753. The next prime is 1021490893. The reversal of 1021490865 is 5680941201.

1021490865 is a `hidden beast` number, since 102 + 1 + 490 + 8 + 65 = 666.

It is not a de Polignac number, because 1021490865 - 2⁸ = 1021490609 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3783165 + ... + 3783434.

It is an arithmetic number, because the mean of its divisors is an integer number (113499000).

Almost surely, 2^1021490865 is an apocalyptic number.

1021490865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1021490865 is a deficient number, since it is larger than the sum of its proper divisors (794493135).

1021490865 is an equidigital number, since it uses as much as digits as its factorization.

1021490865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7566613 (or 7566607 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 1021490865 is about 31960.7707197433. The cubic root of 1021490865 is about 1007.1129082474.

The spelling of 1021490865 in words is "one billion, twenty-one million, four hundred ninety thousand, eight hundred sixty-five".