851623 has 2 divisors, whose sum is σ = 851624. Its totient is φ = 851622.

The previous prime is 851603. The next prime is 851633. The reversal of 851623 is 326158.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-851623 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (851603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 425811 + 425812.

It is an arithmetic number, because the mean of its divisors is an integer number (425812).

2⁸⁵¹⁶²³ is an apocalyptic number.

851623 is a deficient number, since it is larger than the sum of its proper divisors (1).

851623 is an equidigital number, since it uses as much as digits as its factorization.

851623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 25.

The square root of 851623 is about 922.8342212987. The cubic root of 851623 is about 94.7870762231.

The spelling of 851623 in words is "eight hundred fifty-one thousand, six hundred twenty-three".