2154221136 has 80 divisors (see below), whose sum is σ = 6192371520. Its totient is φ = 717033600.

The previous prime is 2154221131. The next prime is 2154221143. The reversal of 2154221136 is 6311224512.

2154221136 is a `hidden beast` number, since 2 + 1 + 542 + 2 + 113 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2154221131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 330711 + ... + 337161.

It is an arithmetic number, because the mean of its divisors is an integer number (77404644).

Almost surely, 2^2154221136 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2154221136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3096185760).

2154221136 is an abundant number, since it is smaller than the sum of its proper divisors (4038150384).

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

2154221136 is a wasteful number, since it uses less digits than its factorization.

2154221136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7241 (or 7229 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 2154221136 is about 46413.5878380459. The cubic root of 2154221136 is about 1291.5069895119.

Adding to 2154221136 its reverse (6311224512), we get a palindrome (8465445648).

The spelling of 2154221136 in words is "two billion, one hundred fifty-four million, two hundred twenty-one thousand, one hundred thirty-six".