21000550351 has 4 divisors (see below), whose sum is σ = 22909691304. Its totient is φ = 19091409400.

The previous prime is 21000550331. The next prime is 21000550369. The reversal of 21000550351 is 15305500012.

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 21000550351 - 2¹³ = 21000542159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000550321) 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, 954570460 + ... + 954570481.

It is an arithmetic number, because the mean of its divisors is an integer number (5727422826).

Almost surely, 2^21000550351 is an apocalyptic number.

21000550351 is a deficient number, since it is larger than the sum of its proper divisors (1909140953).

21000550351 is a wasteful number, since it uses less digits than its factorization.

21000550351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1909140952.

The product of its (nonzero) digits is 750, while the sum is 22.

The spelling of 21000550351 in words is "twenty-one billion, five hundred fifty thousand, three hundred fifty-one".