21000401404 has 24 divisors (see below), whose sum is σ = 37679407920. Its totient is φ = 10235817984.

The previous prime is 21000401399. The next prime is 21000401407. The reversal of 21000401404 is 40410400012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000401407) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32389 + ... + 207484.

It is an arithmetic number, because the mean of its divisors is an integer number (1569975330).

Almost surely, 2^21000401404 is an apocalyptic number.

It is an amenable number.

21000401404 is a deficient number, since it is larger than the sum of its proper divisors (16679006516).

21000401404 is a wasteful number, since it uses less digits than its factorization.

21000401404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240429 (or 240427 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21000401404 its reverse (40410400012), we get a palindrome (61410801416).

The spelling of 21000401404 in words is "twenty-one billion, four hundred one thousand, four hundred four".