21140400441 has 4 divisors (see below), whose sum is σ = 28187200592. Its totient is φ = 14093600292.

The previous prime is 21140400433. The next prime is 21140400461. The reversal of 21140400441 is 14400404112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21140400441 - 2³ = 21140400433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21140400461) 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, 3523400071 + ... + 3523400076.

It is an arithmetic number, because the mean of its divisors is an integer number (7046800148).

Almost surely, 2^21140400441 is an apocalyptic number.

It is an amenable number.

21140400441 is a deficient number, since it is larger than the sum of its proper divisors (7046800151).

21140400441 is an equidigital number, since it uses as much as digits as its factorization.

21140400441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7046800150.

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 21140400441 its reverse (14400404112), we get a palindrome (35540804553).

The spelling of 21140400441 in words is "twenty-one billion, one hundred forty million, four hundred thousand, four hundred forty-one".