647720926 has 4 divisors (see below), whose sum is σ = 971581392. Its totient is φ = 323860462.

The previous prime is 647720923. The next prime is 647720929. The reversal of 647720926 is 629027746.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 629027746 = 2 ⋅314513873.

It is an interprime number because it is at equal distance from previous prime (647720923) and next prime (647720929).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647720923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161930230 + ... + 161930233.

It is an arithmetic number, because the mean of its divisors is an integer number (242895348).

Almost surely, 2^647720926 is an apocalyptic number.

647720926 is a deficient number, since it is larger than the sum of its proper divisors (323860466).

647720926 is a wasteful number, since it uses less digits than its factorization.

647720926 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323860465.

The product of its (nonzero) digits is 254016, while the sum is 43.

The square root of 647720926 is about 25450.3620013547. The cubic root of 647720926 is about 865.2254976934.

The spelling of 647720926 in words is "six hundred forty-seven million, seven hundred twenty thousand, nine hundred twenty-six".