21544520202 has 24 divisors (see below), whose sum is σ = 46685236260. Its totient is φ = 7180669440.

The previous prime is 21544520171. The next prime is 21544520203. The reversal of 21544520202 is 20202544512.

21544520202 is a `hidden beast` number, since 2 + 1 + 5 + 4 + 452 + 0 + 202 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 21479540481 + 64979721 = 146559^2 + 8061^2 .

It is a super-2 number, since 2×21544520202² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21544520203) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 100074 + ... + 230442.

Almost surely, 2^21544520202 is an apocalyptic number.

21544520202 is an abundant number, since it is smaller than the sum of its proper divisors (25140716058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21544520202 is a wasteful number, since it uses less digits than its factorization.

21544520202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139558 (or 139555 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 27.

The spelling of 21544520202 in words is "twenty-one billion, five hundred forty-four million, five hundred twenty thousand, two hundred two".