1201011220 has 24 divisors (see below), whose sum is σ = 2609094600. Its totient is φ = 463838592.

The previous prime is 1201011181. The next prime is 1201011233. The reversal of 1201011220 is 221101021.

It can be written as a sum of positive squares in 4 ways, for example, as 164557584 + 1036453636 = 12828^2 + 32194^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 1201011197 and 1201011206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1034775 + ... + 1035934.

It is an arithmetic number, because the mean of its divisors is an integer number (108712275).

Almost surely, 2^1201011220 is an apocalyptic number.

1201011220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1201011220 is an abundant number, since it is smaller than the sum of its proper divisors (1408083380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1201011220 is a wasteful number, since it uses less digits than its factorization.

1201011220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2070747 (or 2070745 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1201011220 is about 34655.6087812637. The cubic root of 1201011220 is about 1062.9569802647.

Adding to 1201011220 its reverse (221101021), we get a palindrome (1422112241).

The spelling of 1201011220 in words is "one billion, two hundred one million, eleven thousand, two hundred twenty".