1621606 has 12 divisors (see below), whose sum is σ = 2829708. Its totient is φ = 694932.

The previous prime is 1621597. The next prime is 1621619. The reversal of 1621606 is 6061261.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8176 + ... + 8371.

It is an arithmetic number, because the mean of its divisors is an integer number (235809).

2^1621606 is an apocalyptic number.

1621606 is a deficient number, since it is larger than the sum of its proper divisors (1208102).

1621606 is a wasteful number, since it uses less digits than its factorization.

1621606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16563 (or 16556 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 1621606 is about 1273.4229462359. The cubic root of 1621606 is about 117.4848267717.

Adding to 1621606 its reverse (6061261), we get a palindrome (7682867).

It can be divided in two parts, 16 and 21606, that multiplied together give a triangular number (345696 = T₈₃₁).

The spelling of 1621606 in words is "one million, six hundred twenty-one thousand, six hundred six".