21100508494 has 32 divisors (see below), whose sum is σ = 36271972800. Its totient is φ = 9119734272.

The previous prime is 21100508467. The next prime is 21100508503. The reversal of 21100508494 is 49480500112.

It is a happy number.

It is a super-2 number, since 2×21100508494² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31989 + ... + 207904.

It is an arithmetic number, because the mean of its divisors is an integer number (1133499150).

Almost surely, 2^21100508494 is an apocalyptic number.

21100508494 is a deficient number, since it is larger than the sum of its proper divisors (15171464306).

21100508494 is a wasteful number, since it uses less digits than its factorization.

21100508494 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240124.

The product of its (nonzero) digits is 11520, while the sum is 34.

The spelling of 21100508494 in words is "twenty-one billion, one hundred million, five hundred eight thousand, four hundred ninety-four".