25535242551 has 144 divisors (see below), whose sum is σ = 45646723584. Its totient is φ = 12561462144.

The previous prime is 25535242543. The next prime is 25535242571. The reversal of 25535242551 is 15524253552.

It is not a de Polignac number, because 25535242551 - 2³ = 25535242543 is a prime.

It is a super-2 number, since 2×25535242551² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25535242511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 97092046 + ... + 97092308.

It is an arithmetic number, because the mean of its divisors is an integer number (316991136).

Almost surely, 2^25535242551 is an apocalyptic number.

25535242551 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

25535242551 is a deficient number, since it is larger than the sum of its proper divisors (20111481033).

25535242551 is a wasteful number, since it uses less digits than its factorization.

25535242551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410 (or 356 counting only the distinct ones).

The product of its digits is 300000, while the sum is 39.

The spelling of 25535242551 in words is "twenty-five billion, five hundred thirty-five million, two hundred forty-two thousand, five hundred fifty-one".