1161220440 has 64 divisors (see below), whose sum is σ = 3501416160. Its totient is φ = 308080640.

The previous prime is 1161220429. The next prime is 1161220453. The reversal of 1161220440 is 440221611.

It is a happy number.

It is a congruent number.

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, 921 + ... + 48200.

Almost surely, 2^1161220440 is an apocalyptic number.

1161220440 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 1161220440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1750708080).

1161220440 is an abundant number, since it is smaller than the sum of its proper divisors (2340195720).

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

1161220440 is a wasteful number, since it uses less digits than its factorization.

1161220440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49332 (or 49328 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 1161220440 is about 34076.6846978986. The cubic root of 1161220440 is about 1051.0859332060.

The spelling of 1161220440 in words is "one billion, one hundred sixty-one million, two hundred twenty thousand, four hundred forty".