1220656331 has 4 divisors (see below), whose sum is σ = 1220812152. Its totient is φ = 1220500512.

The previous prime is 1220656289. The next prime is 1220656379. The reversal of 1220656331 is 1336560221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1336560221 = 22093 ⋅60497.

It is a cyclic number.

It is not a de Polignac number, because 1220656331 - 2⁶ = 1220656267 is a prime.

It is a super-2 number, since 2×1220656331² = 2980003756820763122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220656294 and 1220656303.

It is not an unprimeable number, because it can be changed into a prime (1220656531) 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, 65501 + ... + 82046.

It is an arithmetic number, because the mean of its divisors is an integer number (305203038).

Almost surely, 2^1220656331 is an apocalyptic number.

1220656331 is a deficient number, since it is larger than the sum of its proper divisors (155821).

1220656331 is an equidigital number, since it uses as much as digits as its factorization.

1220656331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155820.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 1220656331 is about 34937.8924808008. The cubic root of 1220656331 is about 1068.7213103296.

The spelling of 1220656331 in words is "one billion, two hundred twenty million, six hundred fifty-six thousand, three hundred thirty-one".