245861381 has 4 divisors (see below), whose sum is σ = 248117100. Its totient is φ = 243605664.

The previous prime is 245861377. The next prime is 245861389. The reversal of 245861381 is 183168542.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 183168542 = 2 ⋅91584271.

It can be written as a sum of positive squares in 2 ways, for example, as 179292100 + 66569281 = 13390^2 + 8159^2 .

It is a cyclic number.

It is not a de Polignac number, because 245861381 - 2² = 245861377 is a prime.

It is a super-2 number, since 2×245861381² = 120895637334454322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245861389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1127696 + ... + 1127913.

It is an arithmetic number, because the mean of its divisors is an integer number (62029275).

Almost surely, 2^245861381 is an apocalyptic number.

It is an amenable number.

245861381 is a deficient number, since it is larger than the sum of its proper divisors (2255719).

245861381 is a wasteful number, since it uses less digits than its factorization.

245861381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2255718.

The product of its digits is 46080, while the sum is 38.

The square root of 245861381 is about 15679.9675063439. The cubic root of 245861381 is about 626.4649420821.

The spelling of 245861381 in words is "two hundred forty-five million, eight hundred sixty-one thousand, three hundred eighty-one".