646174987 has 2 divisors, whose sum is σ = 646174988. Its totient is φ = 646174986.

The previous prime is 646174931. The next prime is 646175039. The reversal of 646174987 is 789471646.

It is an a-pointer prime, because the next prime (646175039) can be obtained adding 646174987 to its sum of digits (52).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 646174987 - 2¹⁵ = 646142219 is a prime.

It is a super-2 number, since 2×646174987² = 835084227648900338, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (646174927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323087493 + 323087494.

It is an arithmetic number, because the mean of its divisors is an integer number (323087494).

Almost surely, 2^646174987 is an apocalyptic number.

646174987 is a deficient number, since it is larger than the sum of its proper divisors (1).

646174987 is an equidigital number, since it uses as much as digits as its factorization.

646174987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2032128, while the sum is 52.

The square root of 646174987 is about 25419.9722069085. The cubic root of 646174987 is about 864.5365943117.

The spelling of 646174987 in words is "six hundred forty-six million, one hundred seventy-four thousand, nine hundred eighty-seven".