155021434 has 4 divisors (see below), whose sum is σ = 232532154. Its totient is φ = 77510716.

The previous prime is 155021431. The next prime is 155021459. The reversal of 155021434 is 434120551.

It is a happy number.

155021434 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 86545809 + 68475625 = 9303^2 + 8275^2 .

It is a junction number, because it is equal to n+sod(n) for n = 155021399 and 155021408.

It is not an unprimeable number, because it can be changed into a prime (155021431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38755357 + ... + 38755360.

Almost surely, 2^155021434 is an apocalyptic number.

155021434 is a deficient number, since it is larger than the sum of its proper divisors (77510720).

155021434 is an equidigital number, since it uses as much as digits as its factorization.

155021434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77510719.

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 155021434 is about 12450.7603783865. The cubic root of 155021434 is about 537.1932949347.

Adding to 155021434 its reverse (434120551), we get a palindrome (589141985).

The spelling of 155021434 in words is "one hundred fifty-five million, twenty-one thousand, four hundred thirty-four".