21402143523 has 24 divisors (see below), whose sum is σ = 32746896000. Its totient is φ = 13422968064.

The previous prime is 21402143519. The next prime is 21402143527. The reversal of 21402143523 is 32534120412.

It is an interprime number because it is at equal distance from previous prime (21402143519) and next prime (21402143527).

It is not a de Polignac number, because 21402143523 - 2² = 21402143519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21402143527) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 337893 + ... + 396201.

It is an arithmetic number, because the mean of its divisors is an integer number (1364454000).

Almost surely, 2^21402143523 is an apocalyptic number.

21402143523 is a deficient number, since it is larger than the sum of its proper divisors (11344752477).

21402143523 is a wasteful number, since it uses less digits than its factorization.

21402143523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60731 (or 60728 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

Adding to 21402143523 its reverse (32534120412), we get a palindrome (53936263935).

The spelling of 21402143523 in words is "twenty-one billion, four hundred two million, one hundred forty-three thousand, five hundred twenty-three".