21434021051 has 2 divisors, whose sum is σ = 21434021052. Its totient is φ = 21434021050.

The previous prime is 21434021029. The next prime is 21434021111. The reversal of 21434021051 is 15012043412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21434021051 - 2²⁶ = 21366912187 is a prime.

It is a super-2 number, since 2×21434021051² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21434021351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10717010525 + 10717010526.

It is an arithmetic number, because the mean of its divisors is an integer number (10717010526).

Almost surely, 2^21434021051 is an apocalyptic number.

21434021051 is a deficient number, since it is larger than the sum of its proper divisors (1).

21434021051 is an equidigital number, since it uses as much as digits as its factorization.

21434021051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 21434021051 its reverse (15012043412), we get a palindrome (36446064463).

The spelling of 21434021051 in words is "twenty-one billion, four hundred thirty-four million, twenty-one thousand, fifty-one".