21010205425 has 24 divisors (see below), whose sum is σ = 28430983872. Its totient is φ = 15274824000.

The previous prime is 21010205413. The next prime is 21010205459. The reversal of 21010205425 is 52450201012.

It is not a de Polignac number, because 21010205425 - 2⁷ = 21010205297 is a prime.

It is a super-3 number, since 3×21010205425³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21010205396 and 21010205405.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 887847 + ... + 911203.

It is an arithmetic number, because the mean of its divisors is an integer number (1184624328).

Almost surely, 2^21010205425 is an apocalyptic number.

21010205425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21010205425 is a deficient number, since it is larger than the sum of its proper divisors (7420778447).

21010205425 is a wasteful number, since it uses less digits than its factorization.

21010205425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26649 (or 26644 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

Adding to 21010205425 its reverse (52450201012), we get a palindrome (73460406437).

The spelling of 21010205425 in words is "twenty-one billion, ten million, two hundred five thousand, four hundred twenty-five".