21284093951 has 4 divisors (see below), whose sum is σ = 21285995952. Its totient is φ = 21282191952.

The previous prime is 21284093939. The next prime is 21284093983. The reversal of 21284093951 is 15939048212.

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 21284093951 - 2¹⁴ = 21284077567 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 (21284093251) 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, 934115 + ... + 956628.

It is an arithmetic number, because the mean of its divisors is an integer number (5321498988).

Almost surely, 2^21284093951 is an apocalyptic number.

21284093951 is a deficient number, since it is larger than the sum of its proper divisors (1902001).

21284093951 is a wasteful number, since it uses less digits than its factorization.

21284093951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1902000.

The product of its (nonzero) digits is 155520, while the sum is 44.

The spelling of 21284093951 in words is "twenty-one billion, two hundred eighty-four million, ninety-three thousand, nine hundred fifty-one".