71644963 has 4 divisors (see below), whose sum is σ = 77156128. Its totient is φ = 66133800.

The previous prime is 71644961. The next prime is 71644981. The reversal of 71644963 is 36944617.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36944617 = 271 ⋅136327.

It is a cyclic number.

It is not a de Polignac number, because 71644963 - 2¹ = 71644961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71644961) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2755563 + ... + 2755588.

It is an arithmetic number, because the mean of its divisors is an integer number (19289032).

Almost surely, 2^71644963 is an apocalyptic number.

71644963 is a deficient number, since it is larger than the sum of its proper divisors (5511165).

71644963 is a wasteful number, since it uses less digits than its factorization.

71644963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5511164.

The product of its digits is 108864, while the sum is 40.

The square root of 71644963 is about 8464.3347641737. The cubic root of 71644963 is about 415.3318350431.

The spelling of 71644963 in words is "seventy-one million, six hundred forty-four thousand, nine hundred sixty-three".