1550516421 has 4 divisors (see below), whose sum is σ = 2067355232. Its totient is φ = 1033677612.

The previous prime is 1550516377. The next prime is 1550516447. The reversal of 1550516421 is 1246150551.

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.

It is not a de Polignac number, because 1550516421 - 2¹⁰ = 1550515397 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 (1550516321) 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 3 ways as a sum of consecutive naturals, for example, 258419401 + ... + 258419406.

It is an arithmetic number, because the mean of its divisors is an integer number (516838808).

Almost surely, 2^1550516421 is an apocalyptic number.

It is an amenable number.

1550516421 is a deficient number, since it is larger than the sum of its proper divisors (516838811).

1550516421 is an equidigital number, since it uses as much as digits as its factorization.

1550516421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516838810.

The product of its (nonzero) digits is 6000, while the sum is 30.

The square root of 1550516421 is about 39376.5973771224. The cubic root of 1550516421 is about 1157.4230401307.

Adding to 1550516421 its reverse (1246150551), we get a palindrome (2796666972).

The spelling of 1550516421 in words is "one billion, five hundred fifty million, five hundred sixteen thousand, four hundred twenty-one".