999749647 has 4 divisors (see below), whose sum is σ = 1076653480. Its totient is φ = 922845816.

The previous prime is 999749629. The next prime is 999749693. The reversal of 999749647 is 746947999.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 746947999 = 7 ⋅106706857.

It is a cyclic number.

It is not a de Polignac number, because 999749647 - 2⁷ = 999749519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999749747) 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, 38451897 + ... + 38451922.

It is an arithmetic number, because the mean of its divisors is an integer number (269163370).

Almost surely, 2^999749647 is an apocalyptic number.

999749647 is a deficient number, since it is larger than the sum of its proper divisors (76903833).

999749647 is a wasteful number, since it uses less digits than its factorization.

999749647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76903832.

The product of its digits is 30862944, while the sum is 64.

The square root of 999749647 is about 31618.8179254064. The cubic root of 999749647 is about 999.9165420350.

The spelling of 999749647 in words is "nine hundred ninety-nine million, seven hundred forty-nine thousand, six hundred forty-seven".