1621113321 has 16 divisors (see below), whose sum is σ = 2176200000. Its totient is φ = 1073399808.

The previous prime is 1621113271. The next prime is 1621113379. The reversal of 1621113321 is 1233111261.

It is not a de Polignac number, because 1621113321 - 2¹⁴ = 1621096937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1621113121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 669505 + ... + 671921.

It is an arithmetic number, because the mean of its divisors is an integer number (136012500).

Almost surely, 2^1621113321 is an apocalyptic number.

It is an amenable number.

1621113321 is a deficient number, since it is larger than the sum of its proper divisors (555086679).

1621113321 is a wasteful number, since it uses less digits than its factorization.

1621113321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3848.

The product of its digits is 216, while the sum is 21.

The square root of 1621113321 is about 40263.0515609535. The cubic root of 1621113321 is about 1174.7292742210.

Adding to 1621113321 its reverse (1233111261), we get a palindrome (2854224582).

The spelling of 1621113321 in words is "one billion, six hundred twenty-one million, one hundred thirteen thousand, three hundred twenty-one".