100561021542 has 12 divisors (see below), whose sum is σ = 217882213380. Its totient is φ = 33520340508.

The previous prime is 100561021537. The next prime is 100561021549. The reversal of 100561021542 is 245120165001.

100561021542 is a `hidden beast` number, since 1 + 0 + 0 + 5 + 610 + 2 + 1 + 5 + 42 = 666.

It is a super-2 number, since 2×100561021542² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100561021549) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2793361692 + ... + 2793361727.

It is an arithmetic number, because the mean of its divisors is an integer number (18156851115).

Almost surely, 2^100561021542 is an apocalyptic number.

100561021542 is an abundant number, since it is smaller than the sum of its proper divisors (117321191838).

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

100561021542 is a wasteful number, since it uses less digits than its factorization.

100561021542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5586723427 (or 5586723424 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

Adding to 100561021542 its reverse (245120165001), we get a palindrome (345681186543).

The spelling of 100561021542 in words is "one hundred billion, five hundred sixty-one million, twenty-one thousand, five hundred forty-two".