21554241423 has 16 divisors (see below), whose sum is σ = 33763287936. Its totient is φ = 12058316640.

The previous prime is 21554241409. The next prime is 21554241437. The reversal of 21554241423 is 32414245512.

It is an interprime number because it is at equal distance from previous prime (21554241409) and next prime (21554241437).

It is not a de Polignac number, because 21554241423 - 2²² = 21550047119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21554241403) 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, 25121065 + ... + 25121922.

It is an arithmetic number, because the mean of its divisors is an integer number (2110205496).

Almost surely, 2^21554241423 is an apocalyptic number.

21554241423 is a deficient number, since it is larger than the sum of its proper divisors (12209046513).

21554241423 is a wasteful number, since it uses less digits than its factorization.

21554241423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50243014.

The product of its digits is 38400, while the sum is 33.

Adding to 21554241423 its reverse (32414245512), we get a palindrome (53968486935).

The spelling of 21554241423 in words is "twenty-one billion, five hundred fifty-four million, two hundred forty-one thousand, four hundred twenty-three".