1621712106 has 48 divisors (see below), whose sum is σ = 4190269824. Its totient is φ = 443200032.

The previous prime is 1621712069. The next prime is 1621712107. The reversal of 1621712106 is 6012171261.

It is a happy number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1621712106.

It is not an unprimeable number, because it can be changed into a prime (1621712107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 276901 + ... + 282696.

It is an arithmetic number, because the mean of its divisors is an integer number (87297288).

Almost surely, 2^1621712106 is an apocalyptic number.

1621712106 is an abundant number, since it is smaller than the sum of its proper divisors (2568557718).

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

1621712106 is a wasteful number, since it uses less digits than its factorization.

1621712106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559635 (or 559632 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 1621712106 is about 40270.4867862309. The cubic root of 1621712106 is about 1174.8738916415.

Adding to 1621712106 its reverse (6012171261), we get a palindrome (7633883367).

The spelling of 1621712106 in words is "one billion, six hundred twenty-one million, seven hundred twelve thousand, one hundred six".