1285924921 has 8 divisors (see below), whose sum is σ = 1359273600. Its totient is φ = 1213143120.

The previous prime is 1285924901. The next prime is 1285924979. The reversal of 1285924921 is 1294295821.

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 1285924921 - 2⁵ = 1285924889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1285924901) 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, 137050 + ... + 146131.

It is an arithmetic number, because the mean of its divisors is an integer number (169909200).

Almost surely, 2^1285924921 is an apocalyptic number.

It is an amenable number.

1285924921 is a deficient number, since it is larger than the sum of its proper divisors (73348679).

1285924921 is a wasteful number, since it uses less digits than its factorization.

1285924921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283439.

The product of its digits is 103680, while the sum is 43.

The square root of 1285924921 is about 35859.7953284734. The cubic root of 1285924921 is about 1087.4397506763.

The spelling of 1285924921 in words is "one billion, two hundred eighty-five million, nine hundred twenty-four thousand, nine hundred twenty-one".