71644774 has 4 divisors (see below), whose sum is σ = 107467164. Its totient is φ = 35822386.

The previous prime is 71644757. The next prime is 71644777. The reversal of 71644774 is 47744617.

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

It is a super-2 number, since 2×71644774² = 10265947283022152, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71644777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17911192 + ... + 17911195.

It is an arithmetic number, because the mean of its divisors is an integer number (26866791).

Almost surely, 2^71644774 is an apocalyptic number.

71644774 is a deficient number, since it is larger than the sum of its proper divisors (35822390).

71644774 is a wasteful number, since it uses less digits than its factorization.

71644774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35822389.

The product of its digits is 131712, while the sum is 40.

The square root of 71644774 is about 8464.3235996741. The cubic root of 71644774 is about 415.3314698266.

The spelling of 71644774 in words is "seventy-one million, six hundred forty-four thousand, seven hundred seventy-four".