21074638506 has 16 divisors (see below), whose sum is σ = 44628646464. Its totient is φ = 6611651264.

The previous prime is 21074638483. The next prime is 21074638531. The reversal of 21074638506 is 60583647012.

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 7 ways as a sum of consecutive naturals, for example, 103306950 + ... + 103307153.

It is an arithmetic number, because the mean of its divisors is an integer number (2789290404).

Almost surely, 2^21074638506 is an apocalyptic number.

21074638506 is an abundant number, since it is smaller than the sum of its proper divisors (23554007958).

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

21074638506 is a wasteful number, since it uses less digits than its factorization.

21074638506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206614125.

The product of its (nonzero) digits is 241920, while the sum is 42.

The spelling of 21074638506 in words is "twenty-one billion, seventy-four million, six hundred thirty-eight thousand, five hundred six".