21003354625 has 16 divisors (see below), whose sum is σ = 28595114496. Its totient is φ = 15275166000.

The previous prime is 21003354571. The next prime is 21003354677. The reversal of 21003354625 is 52645330012.

It is a happy number.

It is not a de Polignac number, because 21003354625 - 2¹³ = 21003346433 is a prime.

It is a super-2 number, since 2×21003354625² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7636209 + ... + 7638958.

It is an arithmetic number, because the mean of its divisors is an integer number (1787194656).

Almost surely, 2^21003354625 is an apocalyptic number.

21003354625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21003354625 is a deficient number, since it is larger than the sum of its proper divisors (7591759871).

21003354625 is a wasteful number, since it uses less digits than its factorization.

21003354625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15275193 (or 15275183 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 31.

Adding to 21003354625 its reverse (52645330012), we get a palindrome (73648684637).

The spelling of 21003354625 in words is "twenty-one billion, three million, three hundred fifty-four thousand, six hundred twenty-five".