135621025 has 12 divisors (see below), whose sum is σ = 169457904. Its totient is φ = 107666000.

The previous prime is 135620987. The next prime is 135621037. The reversal of 135621025 is 520126531.

It is not a de Polignac number, because 135621025 - 2²⁵ = 102066593 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17431 + ... + 23980.

It is an arithmetic number, because the mean of its divisors is an integer number (14121492).

Almost surely, 2^135621025 is an apocalyptic number.

It is an amenable number.

135621025 is a deficient number, since it is larger than the sum of its proper divisors (33836879).

135621025 is a wasteful number, since it uses less digits than its factorization.

135621025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41552 (or 41547 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 135621025 is about 11645.6440354323. The cubic root of 135621025 is about 513.7782014778.

Adding to 135621025 its reverse (520126531), we get a palindrome (655747556).

The spelling of 135621025 in words is "one hundred thirty-five million, six hundred twenty-one thousand, twenty-five".