1221442785 has 12 divisors (see below), whose sum is σ = 2117167572. Its totient is φ = 651436128.

The previous prime is 1221442777. The next prime is 1221442813. The reversal of 1221442785 is 5872441221.

1221442785 is a `hidden beast` number, since 1 + 221 + 4 + 427 + 8 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 921183201 + 300259584 = 30351^2 + 17328^2 .

It is not a de Polignac number, because 1221442785 - 2³ = 1221442777 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13571542 + ... + 13571631.

It is an arithmetic number, because the mean of its divisors is an integer number (176430631).

Almost surely, 2^1221442785 is an apocalyptic number.

1221442785 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1221442785 is a deficient number, since it is larger than the sum of its proper divisors (895724787).

1221442785 is a wasteful number, since it uses less digits than its factorization.

1221442785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27143184 (or 27143181 counting only the distinct ones).

The product of its digits is 35840, while the sum is 36.

The square root of 1221442785 is about 34949.1456977134. The cubic root of 1221442785 is about 1068.9507824271.

The spelling of 1221442785 in words is "one billion, two hundred twenty-one million, four hundred forty-two thousand, seven hundred eighty-five".