1285783221 has 16 divisors (see below), whose sum is σ = 1733014080. Its totient is φ = 847916160.

The previous prime is 1285783217. The next prime is 1285783231. The reversal of 1285783221 is 1223875821.

It is not a de Polignac number, because 1285783221 - 2² = 1285783217 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1285783221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1285783201) 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, 111691 + ... + 122663.

It is an arithmetic number, because the mean of its divisors is an integer number (108313380).

Almost surely, 2^1285783221 is an apocalyptic number.

It is an amenable number.

1285783221 is a deficient number, since it is larger than the sum of its proper divisors (447230859).

1285783221 is a wasteful number, since it uses less digits than its factorization.

1285783221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11396.

The product of its digits is 53760, while the sum is 39.

The square root of 1285783221 is about 35857.8195237803. The cubic root of 1285783221 is about 1087.3998064384.

The spelling of 1285783221 in words is "one billion, two hundred eighty-five million, seven hundred eighty-three thousand, two hundred twenty-one".