71264632644 has 18 divisors (see below), whose sum is σ = 180141154830. Its totient is φ = 23754877536.

The previous prime is 71264632643. The next prime is 71264632657. The reversal of 71264632644 is 44623646217.

71264632644 is a `hidden beast` number, since 7 + 1 + 2 + 6 + 4 + 632 + 6 + 4 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 39192120900 + 32072511744 = 197970^2 + 179088^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a self number, because there is not a number n which added to its sum of digits gives 71264632644.

It is not an unprimeable number, because it can be changed into a prime (71264632643) 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, 989786529 + ... + 989786600.

It is an arithmetic number, because the mean of its divisors is an integer number (10007841935).

Almost surely, 2^71264632644 is an apocalyptic number.

It is an amenable number.

71264632644 is an abundant number, since it is smaller than the sum of its proper divisors (108876522186).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71264632644 is a wasteful number, since it uses less digits than its factorization.

71264632644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1979573139 (or 1979573134 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 45.

The spelling of 71264632644 in words is "seventy-one billion, two hundred sixty-four million, six hundred thirty-two thousand, six hundred forty-four".