642623497 has 2 divisors, whose sum is σ = 642623498. Its totient is φ = 642623496.

The previous prime is 642623483. The next prime is 642623537. The reversal of 642623497 is 794326246.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 395850816 + 246772681 = 19896^2 + 15709^2 .

It is a cyclic number.

It is not a de Polignac number, because 642623497 - 2⁷ = 642623369 is a prime.

It is not a weakly prime, because it can be changed into another prime (642623447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321311748 + 321311749.

It is an arithmetic number, because the mean of its divisors is an integer number (321311749).

Almost surely, 2^642623497 is an apocalyptic number.

It is an amenable number.

642623497 is a deficient number, since it is larger than the sum of its proper divisors (1).

642623497 is an equidigital number, since it uses as much as digits as its factorization.

642623497 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 43.

The square root of 642623497 is about 25350.0196646867. The cubic root of 642623497 is about 862.9498025457.

The spelling of 642623497 in words is "six hundred forty-two million, six hundred twenty-three thousand, four hundred ninety-seven".