651663 has 12 divisors (see below), whose sum is σ = 957528. Its totient is φ = 426960.

The previous prime is 651649. The next prime is 651667. The reversal of 651663 is 366156.

651663 is a `hidden beast` number, since 651 + 6 + 6 + 3 = 666.

It is not a de Polignac number, because 651663 - 2⁴ = 651647 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 651663.

It is not an unprimeable number, because it can be changed into a prime (651667) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45 + ... + 1142.

It is an arithmetic number, because the mean of its divisors is an integer number (79794).

2⁶⁵¹⁶⁶³ is an apocalyptic number.

651663 is a deficient number, since it is larger than the sum of its proper divisors (305865).

651663 is a wasteful number, since it uses less digits than its factorization.

651663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1254 (or 1251 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 651663 is about 807.2564648239. The cubic root of 651663 is about 86.6977222695.

It can be divided in two parts, 65 and 1663, that added together give a cube (1728 = 12³).

The spelling of 651663 in words is "six hundred fifty-one thousand, six hundred sixty-three".