1621642 has 12 divisors (see below), whose sum is σ = 2674098. Its totient is φ = 737000.

The previous prime is 1621639. The next prime is 1621643. The reversal of 1621642 is 2461261.

It can be written as a sum of positive squares in only one way, i.e., 1437601 + 184041 = 1199^2 + 429^2 .

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (1621643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3109 + ... + 3592.

2^1621642 is an apocalyptic number.

1621642 is a deficient number, since it is larger than the sum of its proper divisors (1052456).

1621642 is a wasteful number, since it uses less digits than its factorization.

1621642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6725 (or 6714 counting only the distinct ones).

The product of its digits is 576, while the sum is 22.

The square root of 1621642 is about 1273.4370812883. The cubic root of 1621642 is about 117.4856961613.

The spelling of 1621642 in words is "one million, six hundred twenty-one thousand, six hundred forty-two".