21443011401 has 16 divisors (see below), whose sum is σ = 32677110144. Its totient is φ = 12252382464.

The previous prime is 21443011399. The next prime is 21443011409. The reversal of 21443011401 is 10411034412.

It is not a de Polignac number, because 21443011401 - 2¹ = 21443011399 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (21443011409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 651595 + ... + 683711.

It is an arithmetic number, because the mean of its divisors is an integer number (2042319384).

Almost surely, 2^21443011401 is an apocalyptic number.

21443011401 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21443011401 is a deficient number, since it is larger than the sum of its proper divisors (11234098743).

21443011401 is a wasteful number, since it uses less digits than its factorization.

21443011401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63920.

The product of its (nonzero) digits is 384, while the sum is 21.

Adding to 21443011401 its reverse (10411034412), we get a palindrome (31854045813).

The spelling of 21443011401 in words is "twenty-one billion, four hundred forty-three million, eleven thousand, four hundred one".