1611413621 has 4 divisors (see below), whose sum is σ = 1611511200. Its totient is φ = 1611316044.

The previous prime is 1611413513. The next prime is 1611413633. The reversal of 1611413621 is 1263141161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1611413621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1611413651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17201 + ... + 59318.

It is an arithmetic number, because the mean of its divisors is an integer number (402877800).

Almost surely, 2^1611413621 is an apocalyptic number.

It is an amenable number.

1611413621 is a deficient number, since it is larger than the sum of its proper divisors (97579).

1611413621 is an equidigital number, since it uses as much as digits as its factorization.

1611413621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97578.

The product of its digits is 864, while the sum is 26.

The square root of 1611413621 is about 40142.4167309344. The cubic root of 1611413621 is about 1172.3816441346.

Adding to 1611413621 its reverse (1263141161), we get a palindrome (2874554782).

The spelling of 1611413621 in words is "one billion, six hundred eleven million, four hundred thirteen thousand, six hundred twenty-one".