21025290001 has 9 divisors (see below), whose sum is σ = 21293847561. Its totient is φ = 20760083172.

The previous prime is 21025289951. The next prime is 21025290023. The reversal of 21025290001 is 10009252012.

The square root of 21025290001 is 145001.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 21025290001 - 2¹¹ = 21025287953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21025290101) by changing a digit.

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 8 ways as a sum of consecutive naturals, for example, 12034210 + ... + 12035956.

Almost surely, 2^21025290001 is an apocalyptic number.

21025290001 is the 145001-st square number.

21025290001 is the 72501-st centered octagonal number.

It is an amenable number.

21025290001 is a deficient number, since it is larger than the sum of its proper divisors (268557560).

21025290001 is an frugal number, since it uses more digits than its factorization.

21025290001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3660 (or 1830 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 22.

The spelling of 21025290001 in words is "twenty-one billion, twenty-five million, two hundred ninety thousand, one".