10521866438 has 4 divisors (see below), whose sum is σ = 15782799660. Its totient is φ = 5260933218.

The previous prime is 10521866431. The next prime is 10521866447. The reversal of 10521866438 is 83466812501.

10521866438 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83466812501 = 83 ⋅1005624247.

It is a super-2 number, since 2×10521866438² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10521866431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2630466608 + ... + 2630466611.

It is an arithmetic number, because the mean of its divisors is an integer number (3945699915).

Almost surely, 2^10521866438 is an apocalyptic number.

10521866438 is a deficient number, since it is larger than the sum of its proper divisors (5260933222).

10521866438 is an equidigital number, since it uses as much as digits as its factorization.

10521866438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5260933221.

The product of its (nonzero) digits is 276480, while the sum is 44.

The spelling of 10521866438 in words is "ten billion, five hundred twenty-one million, eight hundred sixty-six thousand, four hundred thirty-eight".