12161554140 has 96 divisors (see below), whose sum is σ = 34713403200. Its totient is φ = 3180441600.

The previous prime is 12161554099. The next prime is 12161554147. The reversal of 12161554140 is 4145516121.

It is a super-2 number, since 2×12161554140² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 12161554098 and 12161554107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12161554147) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1272580 + ... + 1282100.

It is an arithmetic number, because the mean of its divisors is an integer number (361597950).

Almost surely, 2^12161554140 is an apocalyptic number.

12161554140 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 12161554140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17356701600).

12161554140 is an abundant number, since it is smaller than the sum of its proper divisors (22551849060).

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

12161554140 is a wasteful number, since it uses less digits than its factorization.

12161554140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9943 (or 9941 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 30.

The spelling of 12161554140 in words is "twelve billion, one hundred sixty-one million, five hundred fifty-four thousand, one hundred forty".