21661223036602 has 8 divisors (see below), whose sum is σ = 32493412426356. Its totient is φ = 10830085561152.

The previous prime is 21661223036587. The next prime is 21661223036617. The reversal of 21661223036602 is 20663032216612.

It is an interprime number because it is at equal distance from previous prime (21661223036587) and next prime (21661223036617).

It can be written as a sum of positive squares in 2 ways, for example, as 21105212709681 + 556010326921 = 4594041^2 + 745661^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262927093 + ... + 263009464.

Almost surely, 2^{21661223036602} is an apocalyptic number.

21661223036602 is a deficient number, since it is larger than the sum of its proper divisors (10832189389754).

21661223036602 is a wasteful number, since it uses less digits than its factorization.

21661223036602 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 525957152.

The product of its (nonzero) digits is 186624, while the sum is 40.

The spelling of 21661223036602 in words is "twenty-one trillion, six hundred sixty-one billion, two hundred twenty-three million, thirty-six thousand, six hundred two".