651023 has 4 divisors (see below), whose sum is σ = 654840. Its totient is φ = 647208.

The previous prime is 651019. The next prime is 651029. The reversal of 651023 is 320156.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 651023 - 2² = 651019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 650992 and 651010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1640 + ... + 1997.

It is an arithmetic number, because the mean of its divisors is an integer number (163710).

2⁶⁵¹⁰²³ is an apocalyptic number.

651023 is a deficient number, since it is larger than the sum of its proper divisors (3817).

651023 is a wasteful number, since it uses less digits than its factorization.

651023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3816.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 651023 is about 806.8599630667. The cubic root of 651023 is about 86.6693309503.

Adding to 651023 its reverse (320156), we get a palindrome (971179).

The spelling of 651023 in words is "six hundred fifty-one thousand, twenty-three".