155401405 has 4 divisors (see below), whose sum is σ = 186481692. Its totient is φ = 124321120.

The previous prime is 155401397. The next prime is 155401417. The reversal of 155401405 is 504104551.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 504104551 = 467 ⋅1079453.

It can be written as a sum of positive squares in 2 ways, for example, as 50993881 + 104407524 = 7141^2 + 10218^2 .

It is not a de Polignac number, because 155401405 - 2³ = 155401397 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 155401405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15540136 + ... + 15540145.

It is an arithmetic number, because the mean of its divisors is an integer number (46620423).

Almost surely, 2^155401405 is an apocalyptic number.

It is an amenable number.

155401405 is a deficient number, since it is larger than the sum of its proper divisors (31080287).

155401405 is an equidigital number, since it uses as much as digits as its factorization.

155401405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31080286.

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 155401405 is about 12466.0099871611. The cubic root of 155401405 is about 537.6318393018.

Adding to 155401405 its reverse (504104551), we get a palindrome (659505956).

The spelling of 155401405 in words is "one hundred fifty-five million, four hundred one thousand, four hundred five".