2161743725 has 12 divisors (see below), whose sum is σ = 2681325780. Its totient is φ = 1728902400.

The previous prime is 2161743721. The next prime is 2161743743. The reversal of 2161743725 is 5273471612.

2161743725 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 455310244 + 1706433481 = 21338^2 + 41309^2 .

It is not a de Polignac number, because 2161743725 - 2² = 2161743721 is a prime.

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161743721) 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, 95831 + ... + 116219.

It is an arithmetic number, because the mean of its divisors is an integer number (223443815).

Almost surely, 2^2161743725 is an apocalyptic number.

2161743725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2161743725 is a deficient number, since it is larger than the sum of its proper divisors (519582055).

2161743725 is a wasteful number, since it uses less digits than its factorization.

2161743725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24640 (or 24635 counting only the distinct ones).

The product of its digits is 70560, while the sum is 38.

The square root of 2161743725 is about 46494.5558641009. Note that the first 3 decimals coincide. The cubic root of 2161743725 is about 1293.0085669051.

The spelling of 2161743725 in words is "two billion, one hundred sixty-one million, seven hundred forty-three thousand, seven hundred twenty-five".