155521425 has 12 divisors (see below), whose sum is σ = 257128880. Its totient is φ = 82944720.

The previous prime is 155521409. The next prime is 155521427. The reversal of 155521425 is 524125551.

It is not a de Polignac number, because 155521425 - 2⁴ = 155521409 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 155521392 and 155521401.

It is not an unprimeable number, because it can be changed into a prime (155521427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1036735 + ... + 1036884.

Almost surely, 2^155521425 is an apocalyptic number.

155521425 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

155521425 is a deficient number, since it is larger than the sum of its proper divisors (101607455).

155521425 is a wasteful number, since it uses less digits than its factorization.

155521425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2073632 (or 2073627 counting only the distinct ones).

The product of its digits is 10000, while the sum is 30.

The square root of 155521425 is about 12470.8229479854. The cubic root of 155521425 is about 537.7702120720.

Adding to 155521425 its reverse (524125551), we get a palindrome (679646976).

The spelling of 155521425 in words is "one hundred fifty-five million, five hundred twenty-one thousand, four hundred twenty-five".