21451052530 has 8 divisors (see below), whose sum is σ = 38611894572. Its totient is φ = 8580421008.

The previous prime is 21451052509. The next prime is 21451052533. The reversal of 21451052530 is 3525015412.

It can be written as a sum of positive squares in 2 ways, for example, as 20859736041 + 591316489 = 144429^2 + 24317^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21451052533) 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, 1072552617 + ... + 1072552636.

Almost surely, 2^21451052530 is an apocalyptic number.

21451052530 is a deficient number, since it is larger than the sum of its proper divisors (17160842042).

21451052530 is a wasteful number, since it uses less digits than its factorization.

21451052530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2145105260.

The product of its (nonzero) digits is 6000, while the sum is 28.

Adding to 21451052530 its reverse (3525015412), we get a palindrome (24976067942).

The spelling of 21451052530 in words is "twenty-one billion, four hundred fifty-one million, fifty-two thousand, five hundred thirty".