2121399456 has 48 divisors (see below), whose sum is σ = 6074919648. Its totient is φ = 642848000.

The previous prime is 2121399431. The next prime is 2121399463. The reversal of 2121399456 is 6549931212.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1003395 + ... + 1005506.

It is an arithmetic number, because the mean of its divisors is an integer number (126560826).

Almost surely, 2^2121399456 is an apocalyptic number.

It is an amenable number.

2121399456 is an abundant number, since it is smaller than the sum of its proper divisors (3953520192).

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

2121399456 is a wasteful number, since it uses less digits than its factorization.

2121399456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2008925 (or 2008917 counting only the distinct ones).

The product of its digits is 116640, while the sum is 42.

The square root of 2121399456 is about 46058.6523467633. The cubic root of 2121399456 is about 1284.9142662095.

The spelling of 2121399456 in words is "two billion, one hundred twenty-one million, three hundred ninety-nine thousand, four hundred fifty-six".