21190042625 has 48 divisors (see below), whose sum is σ = 27896384880. Its totient is φ = 16050944000.

The previous prime is 21190042603. The next prime is 21190042639. The reversal of 21190042625 is 52624009112.

It is a Cunningham number, because it is equal to 145568²+1.

It can be written as a sum of positive squares in 24 ways, for example, as 18564607504 + 2625435121 = 136252^2 + 51239^2 .

It is not a de Polignac number, because 21190042625 - 2¹⁸ = 21189780481 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21190042591 and 21190042600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10181585 + ... + 10183665.

It is an arithmetic number, because the mean of its divisors is an integer number (581174685).

Almost surely, 2^21190042625 is an apocalyptic number.

21190042625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21190042625 is a deficient number, since it is larger than the sum of its proper divisors (6706342255).

21190042625 is an equidigital number, since it uses as much as digits as its factorization.

21190042625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2231 (or 2168 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The spelling of 21190042625 in words is "twenty-one billion, one hundred ninety million, forty-two thousand, six hundred twenty-five".