1621025 has 24 divisors (see below), whose sum is σ = 2351040. Its totient is φ = 1085760.

The previous prime is 1621019. The next prime is 1621031. The reversal of 1621025 is 5201261.

It is an interprime number because it is at equal distance from previous prime (1621019) and next prime (1621031).

It is not a de Polignac number, because 1621025 - 2⁶ = 1620961 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 1620994 and 1621012.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10247 + ... + 10403.

It is an arithmetic number, because the mean of its divisors is an integer number (97960).

2^1621025 is an apocalyptic number.

It is an amenable number.

1621025 is a deficient number, since it is larger than the sum of its proper divisors (730015).

1621025 is a wasteful number, since it uses less digits than its factorization.

1621025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 1621025 is about 1273.1948004921. The cubic root of 1621025 is about 117.4707940087.

Adding to 1621025 its reverse (5201261), we get a palindrome (6822286).

It can be divided in two parts, 16 and 21025, that multiplied together give a square (336400 = 580²).

The spelling of 1621025 in words is "one million, six hundred twenty-one thousand, twenty-five".