155421240423 has 4 divisors (see below), whose sum is σ = 207228320568. Its totient is φ = 103614160280.

The previous prime is 155421240421. The next prime is 155421240437. The reversal of 155421240423 is 324042124551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 324042124551 = 3 ⋅108014041517.

It is a cyclic number.

It is not a de Polignac number, because 155421240423 - 2¹ = 155421240421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155421240421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25903540068 + ... + 25903540073.

It is an arithmetic number, because the mean of its divisors is an integer number (51807080142).

Almost surely, 2^155421240423 is an apocalyptic number.

155421240423 is a deficient number, since it is larger than the sum of its proper divisors (51807080145).

155421240423 is an equidigital number, since it uses as much as digits as its factorization.

155421240423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51807080144.

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

Adding to 155421240423 its reverse (324042124551), we get a palindrome (479463364974).

The spelling of 155421240423 in words is "one hundred fifty-five billion, four hundred twenty-one million, two hundred forty thousand, four hundred twenty-three".