2151111400 has 48 divisors (see below), whose sum is σ = 5015666700. Its totient is φ = 857978880.

The previous prime is 2151111397. The next prime is 2151111401. The reversal of 2151111400 is 41111512.

It can be written as a sum of positive squares in 6 ways, for example, as 700872676 + 1450238724 = 26474^2 + 38082^2 .

It is not an unprimeable number, because it can be changed into a prime (2151111401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55366 + ... + 85834.

Almost surely, 2^2151111400 is an apocalyptic number.

2151111400 is a gapful number since it is divisible by the number (20) 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 2151111400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2507833350).

2151111400 is an abundant number, since it is smaller than the sum of its proper divisors (2864555300).

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

2151111400 is a wasteful number, since it uses less digits than its factorization.

2151111400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30838 (or 30829 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 16.

The square root of 2151111400 is about 46380.0754635005. The cubic root of 2151111400 is about 1290.8852365853.

Adding to 2151111400 its reverse (41111512), we get a palindrome (2192222912).

The spelling of 2151111400 in words is "two billion, one hundred fifty-one million, one hundred eleven thousand, four hundred".