1620255 has 32 divisors (see below), whose sum is σ = 3193344. Its totient is φ = 683136.

The previous prime is 1620251. The next prime is 1620257. The reversal of 1620255 is 5520261.

It is not a de Polignac number, because 1620255 - 2² = 1620251 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620251) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 772 + ... + 1958.

It is an arithmetic number, because the mean of its divisors is an integer number (99792).

2^1620255 is an apocalyptic number.

1620255 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1620255 is a deficient number, since it is larger than the sum of its proper divisors (1573089).

1620255 is a wasteful number, since it uses less digits than its factorization.

1620255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1215.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 1620255 is about 1272.8923756548. The cubic root of 1620255 is about 117.4521912034.

The spelling of 1620255 in words is "one million, six hundred twenty thousand, two hundred fifty-five".