646661169 has 96 divisors (see below), whose sum is σ = 1257984000. Its totient is φ = 310020480.

The previous prime is 646661167. The next prime is 646661201. The reversal of 646661169 is 961166646.

It is not a de Polignac number, because 646661169 - 2¹ = 646661167 is a prime.

It is a super-2 number, since 2×646661169² = 836341334984893122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (646661167) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 461532 + ... + 462930.

It is an arithmetic number, because the mean of its divisors is an integer number (13104000).

Almost surely, 2^646661169 is an apocalyptic number.

646661169 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

It is an amenable number.

646661169 is a deficient number, since it is larger than the sum of its proper divisors (611322831).

646661169 is a wasteful number, since it uses less digits than its factorization.

646661169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1475 (or 1472 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 646661169 is about 25429.5334011460. The cubic root of 646661169 is about 864.7533657056.

The spelling of 646661169 in words is "six hundred forty-six million, six hundred sixty-one thousand, one hundred sixty-nine".