61871218 has 4 divisors (see below), whose sum is σ = 92806830. Its totient is φ = 30935608.

The previous prime is 61871213. The next prime is 61871221. The reversal of 61871218 is 81217816.

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., 59490369 + 2380849 = 7713^2 + 1543^2 .

It is not an unprimeable number, because it can be changed into a prime (61871213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15467803 + ... + 15467806.

Almost surely, 2^61871218 is an apocalyptic number.

61871218 is a deficient number, since it is larger than the sum of its proper divisors (30935612).

61871218 is a wasteful number, since it uses less digits than its factorization.

61871218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30935611.

The product of its digits is 5376, while the sum is 34.

The square root of 61871218 is about 7865.8259579017. The cubic root of 61871218 is about 395.5149359611.

The spelling of 61871218 in words is "sixty-one million, eight hundred seventy-one thousand, two hundred eighteen".