155531640401 has 4 divisors (see below), whose sum is σ = 156210818100. Its totient is φ = 154852462704.

The previous prime is 155531640367. The next prime is 155531640443. The reversal of 155531640401 is 104046135551.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 138890382400 + 16641258001 = 372680^2 + 129001^2 .

It is a cyclic number.

It is not a de Polignac number, because 155531640401 - 2⁶ = 155531640337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155531640491) 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, 339588506 + ... + 339588963.

It is an arithmetic number, because the mean of its divisors is an integer number (39052704525).

Almost surely, 2^155531640401 is an apocalyptic number.

It is an amenable number.

155531640401 is a deficient number, since it is larger than the sum of its proper divisors (679177699).

155531640401 is an equidigital number, since it uses as much as digits as its factorization.

155531640401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 679177698.

The product of its (nonzero) digits is 36000, while the sum is 35.

Adding to 155531640401 its reverse (104046135551), we get a palindrome (259577775952).

The spelling of 155531640401 in words is "one hundred fifty-five billion, five hundred thirty-one million, six hundred forty thousand, four hundred one".