21150664542 has 32 divisors (see below), whose sum is σ = 53715974400. Its totient is φ = 6043046904.

The previous prime is 21150664537. The next prime is 21150664559. The reversal of 21150664542 is 24546605112.

21150664542 is a `hidden beast` number, since 2 + 1 + 1 + 5 + 0 + 6 + 645 + 4 + 2 = 666.

It is a super-2 number, since 2×21150664542² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21150664497 and 21150664506.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27976692 + ... + 27977447.

It is an arithmetic number, because the mean of its divisors is an integer number (1678624200).

Almost surely, 2^21150664542 is an apocalyptic number.

21150664542 is an abundant number, since it is smaller than the sum of its proper divisors (32565309858).

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

21150664542 is a wasteful number, since it uses less digits than its factorization.

21150664542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55954157 (or 55954151 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The spelling of 21150664542 in words is "twenty-one billion, one hundred fifty million, six hundred sixty-four thousand, five hundred forty-two".