25919972421 has 24 divisors (see below), whose sum is σ = 40209881184. Its totient is φ = 14808659040.

The previous prime is 25919972411. The next prime is 25919972447. The reversal of 25919972421 is 12427991952.

It is not a de Polignac number, because 25919972421 - 2⁵ = 25919972389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25919972411) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 983806 + ... + 1009808.

It is an arithmetic number, because the mean of its divisors is an integer number (1675411716).

Almost surely, 2^25919972421 is an apocalyptic number.

25919972421 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

25919972421 is a deficient number, since it is larger than the sum of its proper divisors (14289908763).

25919972421 is a wasteful number, since it uses less digits than its factorization.

25919972421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32801 (or 32794 counting only the distinct ones).

The product of its digits is 816480, while the sum is 51.

The spelling of 25919972421 in words is "twenty-five billion, nine hundred nineteen million, nine hundred seventy-two thousand, four hundred twenty-one".