1220285691 has 24 divisors (see below), whose sum is σ = 1806174656. Its totient is φ = 793482480.

The previous prime is 1220285683. The next prime is 1220285699. The reversal of 1220285691 is 1965820221.

It is an interprime number because it is at equal distance from previous prime (1220285683) and next prime (1220285699).

It is not a de Polignac number, because 1220285691 - 2³ = 1220285683 is a prime.

It is a super-4 number, since 4×1220285691⁴ (a number of 37 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1220285699) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 339936 + ... + 343506.

Almost surely, 2^1220285691 is an apocalyptic number.

1220285691 is a deficient number, since it is larger than the sum of its proper divisors (585888965).

1220285691 is a wasteful number, since it uses less digits than its factorization.

1220285691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4503 (or 4500 counting only the distinct ones).

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

The square root of 1220285691 is about 34932.5878085206. The cubic root of 1220285691 is about 1068.6131305592.

The spelling of 1220285691 in words is "one billion, two hundred twenty million, two hundred eighty-five thousand, six hundred ninety-one".