1421821517 has 4 divisors (see below), whose sum is σ = 1422316896. Its totient is φ = 1421326140.

The previous prime is 1421821507. The next prime is 1421821529. The reversal of 1421821517 is 7151281241.

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 a cyclic number.

It is not a de Polignac number, because 1421821517 - 2¹⁰ = 1421820493 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 (1421821507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243359 + ... + 249132.

It is an arithmetic number, because the mean of its divisors is an integer number (355579224).

Almost surely, 2^1421821517 is an apocalyptic number.

It is an amenable number.

1421821517 is a deficient number, since it is larger than the sum of its proper divisors (495379).

1421821517 is an equidigital number, since it uses as much as digits as its factorization.

1421821517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495378.

The product of its digits is 4480, while the sum is 32.

The square root of 1421821517 is about 37707.0486381525. The cubic root of 1421821517 is about 1124.4712621881.

The spelling of 1421821517 in words is "one billion, four hundred twenty-one million, eight hundred twenty-one thousand, five hundred seventeen".