1621879 has 8 divisors (see below), whose sum is σ = 1863680. Its totient is φ = 1382616.

The previous prime is 1621877. The next prime is 1621909. The reversal of 1621879 is 9781261.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1621879 - 2¹ = 1621877 is a prime.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 1042 + ... + 2080.

It is an arithmetic number, because the mean of its divisors is an integer number (232960).

2^1621879 is an apocalyptic number.

1621879 is a deficient number, since it is larger than the sum of its proper divisors (241801).

1621879 is a wasteful number, since it uses less digits than its factorization.

1621879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1269.

The product of its digits is 6048, while the sum is 34.

The square root of 1621879 is about 1273.5301331339. The cubic root of 1621879 is about 117.4914193221.

It can be divided in two parts, 1621 and 879, that added together give a square (2500 = 50²).

The spelling of 1621879 in words is "one million, six hundred twenty-one thousand, eight hundred seventy-nine".