1220773187 has 4 divisors (see below), whose sum is σ = 1222660656. Its totient is φ = 1218885720.

The previous prime is 1220773157. The next prime is 1220773223. The reversal of 1220773187 is 7813770221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1220773187 - 2¹⁸ = 1220511043 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1220773187.

It is not an unprimeable number, because it can be changed into a prime (1220773157) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 942764 + ... + 944057.

It is an arithmetic number, because the mean of its divisors is an integer number (305665164).

Almost surely, 2^1220773187 is an apocalyptic number.

1220773187 is a deficient number, since it is larger than the sum of its proper divisors (1887469).

1220773187 is an equidigital number, since it uses as much as digits as its factorization.

1220773187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1887468.

The product of its (nonzero) digits is 32928, while the sum is 38.

The square root of 1220773187 is about 34939.5647797737. The cubic root of 1220773187 is about 1068.7554128882.

The spelling of 1220773187 in words is "one billion, two hundred twenty million, seven hundred seventy-three thousand, one hundred eighty-seven".