21033622151621 has 4 divisors (see below), whose sum is σ = 21034251877632. Its totient is φ = 21032992425612.

The previous prime is 21033622151557. The next prime is 21033622151639. The reversal of 21033622151621 is 12615122633012.

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 21033622151621 - 2⁶ = 21033622151557 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 (21033622157621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 314812901 + ... + 314879706.

It is an arithmetic number, because the mean of its divisors is an integer number (5258562969408).

Almost surely, 2^{21033622151621} is an apocalyptic number.

It is an amenable number.

21033622151621 is a deficient number, since it is larger than the sum of its proper divisors (629726011).

21033622151621 is an equidigital number, since it uses as much as digits as its factorization.

21033622151621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 629726010.

The product of its (nonzero) digits is 25920, while the sum is 35.

Adding to 21033622151621 its reverse (12615122633012), we get a palindrome (33648744784633).

The spelling of 21033622151621 in words is "twenty-one trillion, thirty-three billion, six hundred twenty-two million, one hundred fifty-one thousand, six hundred twenty-one".