1220172071 has 4 divisors (see below), whose sum is σ = 1262247000. Its totient is φ = 1178097144.

The previous prime is 1220172061. The next prime is 1220172073. The reversal of 1220172071 is 1702710221.

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 1220172071 - 2¹⁰ = 1220171047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220172073) 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, 21037421 + ... + 21037478.

It is an arithmetic number, because the mean of its divisors is an integer number (315561750).

Almost surely, 2^1220172071 is an apocalyptic number.

1220172071 is a deficient number, since it is larger than the sum of its proper divisors (42074929).

1220172071 is an equidigital number, since it uses as much as digits as its factorization.

1220172071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42074928.

The product of its (nonzero) digits is 392, while the sum is 23.

The square root of 1220172071 is about 34930.9614954985. The cubic root of 1220172071 is about 1068.5799635739.

Adding to 1220172071 its reverse (1702710221), we get a palindrome (2922882292).

The spelling of 1220172071 in words is "one billion, two hundred twenty million, one hundred seventy-two thousand, seventy-one".