25535213621 has 4 divisors (see below), whose sum is σ = 25632305952. Its totient is φ = 25438121292.

The previous prime is 25535213573. The next prime is 25535213689. The reversal of 25535213621 is 12631253552.

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 a de Polignac number, because none of the positive numbers 2^k-25535213621 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 (25535213521) 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, 48545771 + ... + 48546296.

It is an arithmetic number, because the mean of its divisors is an integer number (6408076488).

Almost surely, 2^25535213621 is an apocalyptic number.

It is an amenable number.

25535213621 is a deficient number, since it is larger than the sum of its proper divisors (97092331).

25535213621 is an equidigital number, since it uses as much as digits as its factorization.

25535213621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97092330.

The product of its digits is 54000, while the sum is 35.

The spelling of 25535213621 in words is "twenty-five billion, five hundred thirty-five million, two hundred thirteen thousand, six hundred twenty-one".