2155121456 has 40 divisors (see below), whose sum is σ = 4270768320. Its totient is φ = 1053057024.

The previous prime is 2155121447. The next prime is 2155121483. The reversal of 2155121456 is 6541215512.

It is a super-2 number, since 2×2155121456² = 9289096980223119872, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 621680 + ... + 625136.

It is an arithmetic number, because the mean of its divisors is an integer number (106769208).

Almost surely, 2^2155121456 is an apocalyptic number.

It is an amenable number.

2155121456 is a deficient number, since it is larger than the sum of its proper divisors (2115646864).

2155121456 is a wasteful number, since it uses less digits than its factorization.

2155121456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4341 (or 4335 counting only the distinct ones).

The product of its digits is 12000, while the sum is 32.

The square root of 2155121456 is about 46423.2857087906. The cubic root of 2155121456 is about 1291.6868855626.

Adding to 2155121456 its reverse (6541215512), we get a palindrome (8696336968).

The spelling of 2155121456 in words is "two billion, one hundred fifty-five million, one hundred twenty-one thousand, four hundred fifty-six".