21000223025 has 12 divisors (see below), whose sum is σ = 27172463232. Its totient is φ = 16069735440.

The previous prime is 21000223021. The next prime is 21000223031. The reversal of 21000223025 is 52032200012.

It is not a de Polignac number, because 21000223025 - 2² = 21000223021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21000222994 and 21000223012.

It is not an unprimeable number, because it can be changed into a prime (21000223021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18260489 + ... + 18261638.

It is an arithmetic number, because the mean of its divisors is an integer number (2264371936).

Almost surely, 2^21000223025 is an apocalyptic number.

21000223025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21000223025 is a deficient number, since it is larger than the sum of its proper divisors (6172240207).

21000223025 is a wasteful number, since it uses less digits than its factorization.

21000223025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36522160 (or 36522155 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

Adding to 21000223025 its reverse (52032200012), we get a palindrome (73032423037).

The spelling of 21000223025 in words is "twenty-one billion, two hundred twenty-three thousand, twenty-five".