21444032401 has 4 divisors (see below), whose sum is σ = 23393489904. Its totient is φ = 19494574900.

The previous prime is 21444032383. The next prime is 21444032413. The reversal of 21444032401 is 10423044412.

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 a cyclic number.

It is not a de Polignac number, because 21444032401 - 2³¹ = 19296548753 is a prime.

It is a super-3 number, since 3×21444032401³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21444032461) 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, 974728735 + ... + 974728756.

It is an arithmetic number, because the mean of its divisors is an integer number (5848372476).

Almost surely, 2^21444032401 is an apocalyptic number.

It is an amenable number.

21444032401 is a deficient number, since it is larger than the sum of its proper divisors (1949457503).

21444032401 is a wasteful number, since it uses less digits than its factorization.

21444032401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1949457502.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21444032401 its reverse (10423044412), we get a palindrome (31867076813).

The spelling of 21444032401 in words is "twenty-one billion, four hundred forty-four million, thirty-two thousand, four hundred one".