1161640138 has 4 divisors (see below), whose sum is σ = 1742460210. Its totient is φ = 580820068.

The previous prime is 1161640133. The next prime is 1161640147. The reversal of 1161640138 is 8310461611.

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

It can be written as a sum of positive squares in only one way, i.e., 1150769929 + 10870209 = 33923^2 + 3297^2 .

It is not an unprimeable number, because it can be changed into a prime (1161640133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 290410033 + ... + 290410036.

Almost surely, 2^1161640138 is an apocalyptic number.

1161640138 is a deficient number, since it is larger than the sum of its proper divisors (580820072).

1161640138 is an equidigital number, since it uses as much as digits as its factorization.

1161640138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 580820071.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 1161640138 is about 34082.8422817112. The cubic root of 1161640138 is about 1051.2125487084.

The spelling of 1161640138 in words is "one billion, one hundred sixty-one million, six hundred forty thousand, one hundred thirty-eight".