21401127544 has 8 divisors (see below), whose sum is σ = 40127114160. Its totient is φ = 10700563768.

The previous prime is 21401127541. The next prime is 21401127547. The reversal of 21401127544 is 44572110412.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21401127541) and next prime (21401127547).

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21401127541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1337570464 + ... + 1337570479.

It is an arithmetic number, because the mean of its divisors is an integer number (5015889270).

Almost surely, 2^21401127544 is an apocalyptic number.

It is an amenable number.

21401127544 is a deficient number, since it is larger than the sum of its proper divisors (18725986616).

21401127544 is a wasteful number, since it uses less digits than its factorization.

21401127544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2675140949 (or 2675140945 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 31.

Adding to 21401127544 its reverse (44572110412), we get a palindrome (65973237956).

The spelling of 21401127544 in words is "twenty-one billion, four hundred one million, one hundred twenty-seven thousand, five hundred forty-four".