647123447 has 2 divisors, whose sum is σ = 647123448. Its totient is φ = 647123446.

The previous prime is 647123437. The next prime is 647123461. The reversal of 647123447 is 744321746.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 647123447 - 2¹² = 647119351 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 647123447.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (647123437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323561723 + 323561724.

It is an arithmetic number, because the mean of its divisors is an integer number (323561724).

Almost surely, 2^647123447 is an apocalyptic number.

647123447 is a deficient number, since it is larger than the sum of its proper divisors (1).

647123447 is an equidigital number, since it uses as much as digits as its factorization.

647123447 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 38.

The square root of 647123447 is about 25438.6211693952. The cubic root of 647123447 is about 864.9593784036.

The spelling of 647123447 in words is "six hundred forty-seven million, one hundred twenty-three thousand, four hundred forty-seven".