21455452511507 has 4 divisors (see below), whose sum is σ = 24520517156016. Its totient is φ = 18390387867000.

The previous prime is 21455452511483. The next prime is 21455452511531. The reversal of 21455452511507 is 70511525455412.

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

It is an interprime number because it is at equal distance from previous prime (21455452511483) and next prime (21455452511531).

It is a cyclic number.

It is not a de Polignac number, because 21455452511507 - 2³² = 21451157544211 is a prime.

It is a super-2 number, since 2×21455452511507² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21455452510507) 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, 1532532322244 + ... + 1532532322257.

It is an arithmetic number, because the mean of its divisors is an integer number (6130129289004).

Almost surely, 2^{21455452511507} is an apocalyptic number.

21455452511507 is a deficient number, since it is larger than the sum of its proper divisors (3065064644509).

21455452511507 is an equidigital number, since it uses as much as digits as its factorization.

21455452511507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3065064644508.

The product of its (nonzero) digits is 1400000, while the sum is 47.

Adding to 21455452511507 its reverse (70511525455412), we get a palindrome (91966977966919).

The spelling of 21455452511507 in words is "twenty-one trillion, four hundred fifty-five billion, four hundred fifty-two million, five hundred eleven thousand, five hundred seven".