71782138 has 4 divisors (see below), whose sum is σ = 107673210. Its totient is φ = 35891068.

The previous prime is 71782129. The next prime is 71782147. The reversal of 71782138 is 83128717.

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

It is an interprime number because it is at equal distance from previous prime (71782129) and next prime (71782147).

It can be written as a sum of positive squares in only one way, i.e., 56595529 + 15186609 = 7523^2 + 3897^2 .

It is a junction number, because it is equal to n+sod(n) for n = 71782097 and 71782106.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17945533 + ... + 17945536.

Almost surely, 2^71782138 is an apocalyptic number.

71782138 is a deficient number, since it is larger than the sum of its proper divisors (35891072).

71782138 is a wasteful number, since it uses less digits than its factorization.

71782138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35891071.

The product of its digits is 18816, while the sum is 37.

The square root of 71782138 is about 8472.4340068247. The cubic root of 71782138 is about 415.5967376942.

It can be divided in two parts, 7178 and 2138, that added together give a triangular number (9316 = T₁₃₆).

The spelling of 71782138 in words is "seventy-one million, seven hundred eighty-two thousand, one hundred thirty-eight".