1641621 has 8 divisors (see below), whose sum is σ = 2195424. Its totient is φ = 1091120.

The previous prime is 1641617. The next prime is 1641623. The reversal of 1641621 is 1261461.

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 1641621 - 2² = 1641617 is a prime.

It is an Ulam number.

1641621 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1641623) 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, 790 + ... + 1976.

It is an arithmetic number, because the mean of its divisors is an integer number (274428).

2^1641621 is an apocalyptic number.

It is an amenable number.

1641621 is a deficient number, since it is larger than the sum of its proper divisors (553803).

1641621 is a wasteful number, since it uses less digits than its factorization.

1641621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1651.

The product of its digits is 288, while the sum is 21.

The square root of 1641621 is about 1281.2575853434. The cubic root of 1641621 is about 117.9662117183.

The spelling of 1641621 in words is "one million, six hundred forty-one thousand, six hundred twenty-one".