21655212564002 has 8 divisors (see below), whose sum is σ = 32483802885276. Its totient is φ = 10827278268912.

The previous prime is 21655212563951. The next prime is 21655212564047. The reversal of 21655212564002 is 20046521255612.

It can be written as a sum of positive squares in 2 ways, for example, as 21595993828201 + 59218735801 = 4647149^2 + 243349^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21655212564002² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 163924013 + ... + 164056064.

Almost surely, 2^{21655212564002} is an apocalyptic number.

21655212564002 is a deficient number, since it is larger than the sum of its proper divisors (10828590321274).

21655212564002 is a wasteful number, since it uses less digits than its factorization.

21655212564002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328013092.

The product of its (nonzero) digits is 288000, while the sum is 41.

The spelling of 21655212564002 in words is "twenty-one trillion, six hundred fifty-five billion, two hundred twelve million, five hundred sixty-four thousand, two".