646620487 has 2 divisors, whose sum is σ = 646620488. Its totient is φ = 646620486.

The previous prime is 646620467. The next prime is 646620497. The reversal of 646620487 is 784026646.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 646620487 - 2¹¹ = 646618439 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646620467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323310243 + 323310244.

It is an arithmetic number, because the mean of its divisors is an integer number (323310244).

Almost surely, 2^646620487 is an apocalyptic number.

646620487 is a deficient number, since it is larger than the sum of its proper divisors (1).

646620487 is an equidigital number, since it uses as much as digits as its factorization.

646620487 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 387072, while the sum is 43.

The square root of 646620487 is about 25428.7334918592. The cubic root of 646620487 is about 864.7352312039.

The spelling of 646620487 in words is "six hundred forty-six million, six hundred twenty thousand, four hundred eighty-seven".