21604244720367 has 16 divisors (see below), whose sum is σ = 28904721941088. Its totient is φ = 14353301207040.

The previous prime is 21604244720353. The next prime is 21604244720371. The reversal of 21604244720367 is 76302744240612.

It is not a de Polignac number, because 21604244720367 - 2⁴ = 21604244720351 is a prime.

It is a super-2 number, since 2×21604244720367² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21604244720347) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35945767 + ... + 36541847.

It is an arithmetic number, because the mean of its divisors is an integer number (1806545121318).

Almost surely, 2^{21604244720367} is an apocalyptic number.

21604244720367 is a deficient number, since it is larger than the sum of its proper divisors (7300477220721).

21604244720367 is a wasteful number, since it uses less digits than its factorization.

21604244720367 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637610.

The product of its (nonzero) digits is 2709504, while the sum is 48.

Adding to 21604244720367 its reverse (76302744240612), we get a palindrome (97906988960979).

The spelling of 21604244720367 in words is "twenty-one trillion, six hundred four billion, two hundred forty-four million, seven hundred twenty thousand, three hundred sixty-seven".