155421814 has 4 divisors (see below), whose sum is σ = 233132724. Its totient is φ = 77710906.

The previous prime is 155421797. The next prime is 155421869. The reversal of 155421814 is 418124551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 418124551 = 13 ⋅32163427.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38855452 + ... + 38855455.

It is an arithmetic number, because the mean of its divisors is an integer number (58283181).

Almost surely, 2^155421814 is an apocalyptic number.

155421814 is a deficient number, since it is larger than the sum of its proper divisors (77710910).

155421814 is an equidigital number, since it uses as much as digits as its factorization.

155421814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77710909.

The product of its digits is 6400, while the sum is 31.

The square root of 155421814 is about 12466.8285461861. The cubic root of 155421814 is about 537.6553741553.

The spelling of 155421814 in words is "one hundred fifty-five million, four hundred twenty-one thousand, eight hundred fourteen".