1620775 has 12 divisors (see below), whose sum is σ = 2164792. Its totient is φ = 1196640.

The previous prime is 1620769. The next prime is 1620803. The reversal of 1620775 is 5770261.

1620775 = 20² + 21² + ... + 169².

It is not a de Polignac number, because 1620775 - 2⁵ = 1620743 is a prime.

It is a Duffinian number.

1620775 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2169 + ... + 2818.

2^1620775 is an apocalyptic number.

1620775 is a deficient number, since it is larger than the sum of its proper divisors (544017).

1620775 is a wasteful number, since it uses less digits than its factorization.

1620775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5010 (or 5005 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 1620775 is about 1273.0966184858. The cubic root of 1620775 is about 117.4647547828.

The spelling of 1620775 in words is "one million, six hundred twenty thousand, seven hundred seventy-five".