21858828738 has 16 divisors (see below), whose sum is σ = 43722697536. Its totient is φ = 7285436240.

The previous prime is 21858828737. The next prime is 21858828767. The reversal of 21858828738 is 83782885812.

It is not an unprimeable number, because it can be changed into a prime (21858828737) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 152406 + ... + 258737.

It is an arithmetic number, because the mean of its divisors is an integer number (2732668596).

Almost surely, 2^21858828738 is an apocalyptic number.

21858828738 is an abundant number, since it is smaller than the sum of its proper divisors (21863868798).

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

21858828738 is a wasteful number, since it uses less digits than its factorization.

21858828738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 420009.

The product of its digits is 13762560, while the sum is 60.

The spelling of 21858828738 in words is "twenty-one billion, eight hundred fifty-eight million, eight hundred twenty-eight thousand, seven hundred thirty-eight".