1621698 has 32 divisors (see below), whose sum is σ = 3701376. Its totient is φ = 469248.

The previous prime is 1621679. The next prime is 1621699. The reversal of 1621698 is 8961261.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1621699) 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 15 ways as a sum of consecutive naturals, for example, 715 + ... + 1937.

It is an arithmetic number, because the mean of its divisors is an integer number (115668).

2^1621698 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1621698, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1850688).

1621698 is an abundant number, since it is smaller than the sum of its proper divisors (2079678).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1621698 is a wasteful number, since it uses less digits than its factorization.

1621698 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1258.

The product of its digits is 5184, while the sum is 33.

The square root of 1621698 is about 1273.4590688357. The cubic root of 1621698 is about 117.4870485197.

The spelling of 1621698 in words is "one million, six hundred twenty-one thousand, six hundred ninety-eight".