641878747 has 2 divisors, whose sum is σ = 641878748. Its totient is φ = 641878746.

The previous prime is 641878723. The next prime is 641878753. The reversal of 641878747 is 747878146.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 641878747 - 2¹¹ = 641876699 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 641878694 and 641878703.

It is not a weakly prime, because it can be changed into another prime (641878147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320939373 + 320939374.

It is an arithmetic number, because the mean of its divisors is an integer number (320939374).

Almost surely, 2^641878747 is an apocalyptic number.

641878747 is a deficient number, since it is larger than the sum of its proper divisors (1).

641878747 is an equidigital number, since it uses as much as digits as its factorization.

641878747 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2107392, while the sum is 52.

The square root of 641878747 is about 25335.3260685549. The cubic root of 641878747 is about 862.6163100725.

The spelling of 641878747 in words is "six hundred forty-one million, eight hundred seventy-eight thousand, seven hundred forty-seven".