25510552421 has 4 divisors (see below), whose sum is σ = 25512439200. Its totient is φ = 25508665644.

The previous prime is 25510552349. The next prime is 25510552439. The reversal of 25510552421 is 12425501552.

It is a happy number.

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 25510552421 - 2¹⁰ = 25510551397 is a prime.

It is a super-2 number, since 2×25510552421² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25510552021) 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, 922961 + ... + 950198.

It is an arithmetic number, because the mean of its divisors is an integer number (6378109800).

Almost surely, 2^25510552421 is an apocalyptic number.

It is an amenable number.

25510552421 is a deficient number, since it is larger than the sum of its proper divisors (1886779).

25510552421 is a wasteful number, since it uses less digits than its factorization.

25510552421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1886778.

The product of its (nonzero) digits is 20000, while the sum is 32.

The spelling of 25510552421 in words is "twenty-five billion, five hundred ten million, five hundred fifty-two thousand, four hundred twenty-one".