1621875 has 24 divisors (see below), whose sum is σ = 2718576. Its totient is φ = 860000.

The previous prime is 1621871. The next prime is 1621877. The reversal of 1621875 is 5781261.

1621875 = T₄₁ + T₄₂ + ... + T₂₁₃.

It is not a de Polignac number, because 1621875 - 2² = 1621871 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1621871) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9289 + ... + 9461.

It is an arithmetic number, because the mean of its divisors is an integer number (113274).

2^1621875 is an apocalyptic number.

1621875 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1621875 is a deficient number, since it is larger than the sum of its proper divisors (1096701).

1621875 is an frugal number, since it uses more digits than its factorization.

1621875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 201 (or 181 counting only the distinct ones).

The product of its digits is 3360, while the sum is 30.

The square root of 1621875 is about 1273.5285626950. The cubic root of 1621875 is about 117.4913227333.

The spelling of 1621875 in words is "one million, six hundred twenty-one thousand, eight hundred seventy-five".