2165772137 has 4 divisors (see below), whose sum is σ = 2293170516. Its totient is φ = 2038373760.

The previous prime is 2165772131. The next prime is 2165772149. The reversal of 2165772137 is 7312775612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 834689881 + 1331082256 = 28891^2 + 36484^2 .

It is a cyclic number.

It is not a de Polignac number, because 2165772137 - 2⁶ = 2165772073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2165772094 and 2165772103.

It is not an unprimeable number, because it can be changed into a prime (2165772131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63699164 + ... + 63699197.

It is an arithmetic number, because the mean of its divisors is an integer number (573292629).

Almost surely, 2^2165772137 is an apocalyptic number.

It is an amenable number.

2165772137 is a deficient number, since it is larger than the sum of its proper divisors (127398379).

2165772137 is a wasteful number, since it uses less digits than its factorization.

2165772137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127398378.

The product of its digits is 123480, while the sum is 41.

The square root of 2165772137 is about 46537.8570305939. The cubic root of 2165772137 is about 1293.8112428491.

The spelling of 2165772137 in words is "two billion, one hundred sixty-five million, seven hundred seventy-two thousand, one hundred thirty-seven".