155421983 has 2 divisors, whose sum is σ = 155421984. Its totient is φ = 155421982.

The previous prime is 155421949. The next prime is 155422009. The reversal of 155421983 is 389124551.

It is a happy number.

155421983 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 155421983 - 2¹² = 155417887 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155421913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77710991 + 77710992.

It is an arithmetic number, because the mean of its divisors is an integer number (77710992).

Almost surely, 2^155421983 is an apocalyptic number.

155421983 is a deficient number, since it is larger than the sum of its proper divisors (1).

155421983 is an equidigital number, since it uses as much as digits as its factorization.

155421983 is an evil number, because the sum of its binary digits is even.

The product of its digits is 43200, while the sum is 38.

The square root of 155421983 is about 12466.8353241711. The cubic root of 155421983 is about 537.6555690308.

The spelling of 155421983 in words is "one hundred fifty-five million, four hundred twenty-one thousand, nine hundred eighty-three".