1628993 has 4 divisors (see below), whose sum is σ = 1637460. Its totient is φ = 1620528.

The previous prime is 1628989. The next prime is 1629007. The reversal of 1628993 is 3998261.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1555009 + 73984 = 1247^2 + 272^2 .

It is a cyclic number.

It is not a de Polignac number, because 1628993 - 2² = 1628989 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1628933) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3938 + ... + 4331.

It is an arithmetic number, because the mean of its divisors is an integer number (409365).

2^1628993 is an apocalyptic number.

It is an amenable number.

1628993 is a deficient number, since it is larger than the sum of its proper divisors (8467).

1628993 is an equidigital number, since it uses as much as digits as its factorization.

1628993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8466.

The product of its digits is 23328, while the sum is 38.

The square root of 1628993 is about 1276.3201009151. The cubic root of 1628993 is about 117.6629518186.

The spelling of 1628993 in words is "one million, six hundred twenty-eight thousand, nine hundred ninety-three".