25160421521 has 4 divisors (see below), whose sum is σ = 25286856000. Its totient is φ = 25033987044.

The previous prime is 25160421479. The next prime is 25160421529. The reversal of 25160421521 is 12512406152.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25160421521 - 2⁶ = 25160421457 is a prime.

It is a super-2 number, since 2×25160421521² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25160421529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63216941 + ... + 63217338.

It is an arithmetic number, because the mean of its divisors is an integer number (6321714000).

Almost surely, 2^25160421521 is an apocalyptic number.

It is an amenable number.

25160421521 is a deficient number, since it is larger than the sum of its proper divisors (126434479).

25160421521 is a wasteful number, since it uses less digits than its factorization.

25160421521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126434478.

The product of its (nonzero) digits is 4800, while the sum is 29.

Adding to 25160421521 its reverse (12512406152), we get a palindrome (37672827673).

The spelling of 25160421521 in words is "twenty-five billion, one hundred sixty million, four hundred twenty-one thousand, five hundred twenty-one".