115385781 has 16 divisors (see below), whose sum is σ = 176390784. Its totient is φ = 65722944.

The previous prime is 115385773. The next prime is 115385827. The reversal of 115385781 is 187583511.

It is a happy number.

It is not a de Polignac number, because 115385781 - 2³ = 115385773 is a prime.

It is a super-2 number, since 2×115385781² = 26627756913959922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115385701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2010 + ... + 15323.

It is an arithmetic number, because the mean of its divisors is an integer number (11024424).

Almost surely, 2^115385781 is an apocalyptic number.

It is an amenable number.

115385781 is a deficient number, since it is larger than the sum of its proper divisors (61005003).

115385781 is a wasteful number, since it uses less digits than its factorization.

115385781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17660.

The product of its digits is 33600, while the sum is 39.

The square root of 115385781 is about 10741.7773668979. Note that the first 3 decimals coincide. The cubic root of 115385781 is about 486.8375834171.

The spelling of 115385781 in words is "one hundred fifteen million, three hundred eighty-five thousand, seven hundred eighty-one".