2121641024521 has 4 divisors (see below), whose sum is σ = 2151523292544. Its totient is φ = 2091758756500.

The previous prime is 2121641024453. The next prime is 2121641024563. The reversal of 2121641024521 is 1254201461212.

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 a de Polignac number, because none of the positive numbers 2^k-2121641024521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121641027521) 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, 14941133905 + ... + 14941134046.

It is an arithmetic number, because the mean of its divisors is an integer number (537880823136).

Almost surely, 2^{2121641024521} is an apocalyptic number.

It is an amenable number.

2121641024521 is a deficient number, since it is larger than the sum of its proper divisors (29882268023).

2121641024521 is an equidigital number, since it uses as much as digits as its factorization.

2121641024521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29882268022.

The product of its (nonzero) digits is 7680, while the sum is 31.

Adding to 2121641024521 its reverse (1254201461212), we get a palindrome (3375842485733).

The spelling of 2121641024521 in words is "two trillion, one hundred twenty-one billion, six hundred forty-one million, twenty-four thousand, five hundred twenty-one".