61161813 has 6 divisors (see below), whose sum is σ = 88344854. Its totient is φ = 40774536.

The previous prime is 61161811. The next prime is 61161823. The reversal of 61161813 is 31816116.

It can be written as a sum of positive squares in only one way, i.e., 43797924 + 17363889 = 6618^2 + 4167^2 .

It is not a de Polignac number, because 61161813 - 2¹ = 61161811 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61161811) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3397870 + ... + 3397887.

Almost surely, 2^61161813 is an apocalyptic number.

It is an amenable number.

61161813 is a deficient number, since it is larger than the sum of its proper divisors (27183041).

61161813 is a wasteful number, since it uses less digits than its factorization.

61161813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6795763 (or 6795760 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 61161813 is about 7820.6018310613. The cubic root of 61161813 is about 393.9974855328.

Adding to 61161813 its reverse (31816116), we get a palindrome (92977929).

The spelling of 61161813 in words is "sixty-one million, one hundred sixty-one thousand, eight hundred thirteen".