21350777899 has 4 divisors (see below), whose sum is σ = 23291757720. Its totient is φ = 19409798080.

The previous prime is 21350777891. The next prime is 21350777953. The reversal of 21350777899 is 99877705312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21350777899 - 2³ = 21350777891 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21350777891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 970489894 + ... + 970489915.

It is an arithmetic number, because the mean of its divisors is an integer number (5822939430).

Almost surely, 2^21350777899 is an apocalyptic number.

21350777899 is a deficient number, since it is larger than the sum of its proper divisors (1940979821).

21350777899 is a wasteful number, since it uses less digits than its factorization.

21350777899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1940979820.

The product of its (nonzero) digits is 6667920, while the sum is 58.

The spelling of 21350777899 in words is "twenty-one billion, three hundred fifty million, seven hundred seventy-seven thousand, eight hundred ninety-nine".