1421221621 has 4 divisors (see below), whose sum is σ = 1442433952. Its totient is φ = 1400009292.

The previous prime is 1421221577. The next prime is 1421221639. The reversal of 1421221621 is 1261221241.

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 1421221621 - 2¹³ = 1421213429 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1421221592 and 1421221601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1421221661) 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, 10606065 + ... + 10606198.

It is an arithmetic number, because the mean of its divisors is an integer number (360608488).

Almost surely, 2^1421221621 is an apocalyptic number.

It is an amenable number.

1421221621 is a deficient number, since it is larger than the sum of its proper divisors (21212331).

1421221621 is an equidigital number, since it uses as much as digits as its factorization.

1421221621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21212330.

The product of its digits is 384, while the sum is 22.

The square root of 1421221621 is about 37699.0931058030. The cubic root of 1421221621 is about 1124.3130940220.

Adding to 1421221621 its reverse (1261221241), we get a palindrome (2682442862).

The spelling of 1421221621 in words is "one billion, four hundred twenty-one million, two hundred twenty-one thousand, six hundred twenty-one".