25515000421 has 8 divisors (see below), whose sum is σ = 26870806080. Its totient is φ = 24160485888.

The previous prime is 25515000397. The next prime is 25515000437. The reversal of 25515000421 is 12400051552.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25515000421 - 2²³ = 25506611813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25515000521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 282076 + ... + 361381.

It is an arithmetic number, because the mean of its divisors is an integer number (3358850760).

Almost surely, 2^25515000421 is an apocalyptic number.

It is an amenable number.

25515000421 is a deficient number, since it is larger than the sum of its proper divisors (1355805659).

25515000421 is a wasteful number, since it uses less digits than its factorization.

25515000421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 645563.

The product of its (nonzero) digits is 2000, while the sum is 25.

Adding to 25515000421 its reverse (12400051552), we get a palindrome (37915051973).

The spelling of 25515000421 in words is "twenty-five billion, five hundred fifteen million, four hundred twenty-one", and thus it is an aban number.