861628 has 12 divisors (see below), whose sum is σ = 1596672. Its totient is φ = 405440.

The previous prime is 861617. The next prime is 861647. The reversal of 861628 is 826168.

It is a self number, because there is not a number n which added to its sum of digits gives 861628.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6268 + ... + 6403.

It is an arithmetic number, because the mean of its divisors is an integer number (133056).

2⁸⁶¹⁶²⁸ is an apocalyptic number.

It is an amenable number.

861628 is a deficient number, since it is larger than the sum of its proper divisors (735044).

861628 is a wasteful number, since it uses less digits than its factorization.

861628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12692 (or 12690 counting only the distinct ones).

The product of its digits is 4608, while the sum is 31.

The square root of 861628 is about 928.2391933117. The cubic root of 861628 is about 95.1568231577.

The spelling of 861628 in words is "eight hundred sixty-one thousand, six hundred twenty-eight".