1621115121 has 16 divisors (see below), whose sum is σ = 2295216000. Its totient is φ = 1014244608.

The previous prime is 1621115107. The next prime is 1621115123. The reversal of 1621115121 is 1215111261.

It is not a de Polignac number, because 1621115121 - 2⁶ = 1621115057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1621115123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27741 + ... + 63338.

It is an arithmetic number, because the mean of its divisors is an integer number (143451000).

Almost surely, 2^1621115121 is an apocalyptic number.

It is an amenable number.

1621115121 is a deficient number, since it is larger than the sum of its proper divisors (674100879).

1621115121 is a wasteful number, since it uses less digits than its factorization.

1621115121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91448.

The product of its digits is 120, while the sum is 21.

The square root of 1621115121 is about 40263.0739139475. The cubic root of 1621115121 is about 1174.7297090069.

Adding to 1621115121 its reverse (1215111261), we get a palindrome (2836226382).

The spelling of 1621115121 in words is "one billion, six hundred twenty-one million, one hundred fifteen thousand, one hundred twenty-one".