2131517100 has 72 divisors (see below), whose sum is σ = 6191978688. Its totient is φ = 566120000.

The previous prime is 2131517077. The next prime is 2131517117. The reversal of 2131517100 is 17151312.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61147 + ... + 89453.

It is an arithmetic number, because the mean of its divisors is an integer number (85999704).

Almost surely, 2^2131517100 is an apocalyptic number.

2131517100 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 2131517100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3095989344).

2131517100 is an abundant number, since it is smaller than the sum of its proper divisors (4060461588).

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

2131517100 is a wasteful number, since it uses less digits than its factorization.

2131517100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28575 (or 28568 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 21.

The square root of 2131517100 is about 46168.3560461059. The cubic root of 2131517100 is about 1286.9537520005.

Adding to 2131517100 its reverse (17151312), we get a palindrome (2148668412).

It can be divided in two parts, 21315 and 17100, that multiplied together give a triangular number (364486500 = T₂₆₉₉₉).

The spelling of 2131517100 in words is "two billion, one hundred thirty-one million, five hundred seventeen thousand, one hundred".