21530511400404 has 24 divisors (see below), whose sum is σ = 53193028166208. Its totient is φ = 6754670243200.

The previous prime is 21530511400399. The next prime is 21530511400423. The reversal of 21530511400404 is 40400411503512.

It is a super-2 number, since 2×21530511400404² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52770861072 + ... + 52770861479.

It is an arithmetic number, because the mean of its divisors is an integer number (2216376173592).

Almost surely, 2^{21530511400404} is an apocalyptic number.

It is an amenable number.

21530511400404 is an abundant number, since it is smaller than the sum of its proper divisors (31662516765804).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21530511400404 is a wasteful number, since it uses less digits than its factorization.

21530511400404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105541722575 (or 105541722573 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

Adding to 21530511400404 its reverse (40400411503512), we get a palindrome (61930922903916).

The spelling of 21530511400404 in words is "twenty-one trillion, five hundred thirty billion, five hundred eleven million, four hundred thousand, four hundred four".