155634561 has 32 divisors (see below), whose sum is σ = 240768000. Its totient is φ = 99235584.

The previous prime is 155634509. The next prime is 155634569. The reversal of 155634561 is 165436551.

155634561 is a `hidden beast` number, since 1 + 556 + 3 + 45 + 61 = 666.

It is not a de Polignac number, because 155634561 - 2¹⁸ = 155372417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (155634569) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87600 + ... + 89358.

It is an arithmetic number, because the mean of its divisors is an integer number (7524000).

Almost surely, 2^155634561 is an apocalyptic number.

It is an amenable number.

155634561 is a deficient number, since it is larger than the sum of its proper divisors (85133439).

155634561 is a wasteful number, since it uses less digits than its factorization.

155634561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1910 (or 1904 counting only the distinct ones).

The product of its digits is 54000, while the sum is 36.

The square root of 155634561 is about 12475.3581511715. The cubic root of 155634561 is about 537.9005830128.

The spelling of 155634561 in words is "one hundred fifty-five million, six hundred thirty-four thousand, five hundred sixty-one".