1201661120 has 112 divisors (see below), whose sum is σ = 3133941408. Its totient is φ = 435240960.

The previous prime is 1201661107. The next prime is 1201661141. The reversal of 1201661120 is 211661021.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1201661092 and 1201661101.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1185734 + ... + 1186746.

Almost surely, 2^1201661120 is an apocalyptic number.

1201661120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1201661120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1566970704).

1201661120 is an abundant number, since it is smaller than the sum of its proper divisors (1932280288).

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

1201661120 is a wasteful number, since it uses less digits than its factorization.

1201661120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378 (or 1368 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 1201661120 is about 34664.9840617301. The cubic root of 1201661120 is about 1063.1486773838.

Subtracting from 1201661120 its reverse (211661021), we obtain a palindrome (990000099).

The spelling of 1201661120 in words is "one billion, two hundred one million, six hundred sixty-one thousand, one hundred twenty".