12121221040 has 40 divisors (see below), whose sum is σ = 28781461440. Its totient is φ = 4745327616.

The previous prime is 12121221011. The next prime is 12121221041. The reversal of 12121221040 is 4012212121.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (12121221041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1608105 + ... + 1615624.

It is an arithmetic number, because the mean of its divisors is an integer number (719536536).

Almost surely, 2^12121221040 is an apocalyptic number.

12121221040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12121221040 is an abundant number, since it is smaller than the sum of its proper divisors (16660240400).

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

12121221040 is a wasteful number, since it uses less digits than its factorization.

12121221040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3223789 (or 3223783 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 12121221040 its reverse (4012212121), we get a palindrome (16133433161).

The spelling of 12121221040 in words is "twelve billion, one hundred twenty-one million, two hundred twenty-one thousand, forty".