21604006217629 has 4 divisors (see below), whose sum is σ = 23568006782880. Its totient is φ = 19640005652380.

The previous prime is 21604006217609. The next prime is 21604006217653. The reversal of 21604006217629 is 92671260040612.

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 21604006217629 - 2³⁵ = 21569646479261 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 (21604006217609) 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, 982000282609 + ... + 982000282630.

It is an arithmetic number, because the mean of its divisors is an integer number (5892001695720).

Almost surely, 2^{21604006217629} is an apocalyptic number.

It is an amenable number.

21604006217629 is a deficient number, since it is larger than the sum of its proper divisors (1964000565251).

21604006217629 is a wasteful number, since it uses less digits than its factorization.

21604006217629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1964000565250.

The product of its (nonzero) digits is 435456, while the sum is 46.

The spelling of 21604006217629 in words is "twenty-one trillion, six hundred four billion, six million, two hundred seventeen thousand, six hundred twenty-nine".