155435921 has 2 divisors, whose sum is σ = 155435922. Its totient is φ = 155435920.

The previous prime is 155435873. The next prime is 155435933. The reversal of 155435921 is 129534551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87142225 + 68293696 = 9335^2 + 8264^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155435921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (155435971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77717960 + 77717961.

It is an arithmetic number, because the mean of its divisors is an integer number (77717961).

Almost surely, 2^155435921 is an apocalyptic number.

It is an amenable number.

155435921 is a deficient number, since it is larger than the sum of its proper divisors (1).

155435921 is an equidigital number, since it uses as much as digits as its factorization.

155435921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27000, while the sum is 35.

The square root of 155435921 is about 12467.3943147716. The cubic root of 155435921 is about 537.6716405869.

The spelling of 155435921 in words is "one hundred fifty-five million, four hundred thirty-five thousand, nine hundred twenty-one".