749638471681 has 4 divisors (see below), whose sum is σ = 817787423664. Its totient is φ = 681489519700.

The previous prime is 749638471663. The next prime is 749638471693. The reversal of 749638471681 is 186174836947.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 186174836947 = 11 ⋅16924985177.

It is not a de Polignac number, because 749638471681 - 2⁵ = 749638471649 is a prime.

It is a super-2 number, since 2×749638471681² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (749638471651) 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, 34074475975 + ... + 34074475996.

It is an arithmetic number, because the mean of its divisors is an integer number (204446855916).

Almost surely, 2^749638471681 is an apocalyptic number.

It is an amenable number.

749638471681 is a deficient number, since it is larger than the sum of its proper divisors (68148951983).

749638471681 is a wasteful number, since it uses less digits than its factorization.

749638471681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68148951982.

The product of its digits is 48771072, while the sum is 64.

The spelling of 749638471681 in words is "seven hundred forty-nine billion, six hundred thirty-eight million, four hundred seventy-one thousand, six hundred eighty-one".