21054011056225 has 81 divisors (see below), whose sum is σ = 31388016685401. Its totient is φ = 13968021614400.

The previous prime is 21054011056201. The next prime is 21054011056249. The reversal of 21054011056225 is 52265011045012.

The square root of 21054011056225 is 4588465.

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

It is an interprime number because it is at equal distance from previous prime (21054011056201) and next prime (21054011056249).

It can be written as a sum of positive squares in 4 ways, for example, as 6361447440481 + 14692563615744 = 2522191^2 + 3833088^2 .

It is not a de Polignac number, because 21054011056225 - 2¹⁵ = 21054011023457 is a prime.

It is a super-2 number, since 2×21054011056225² (a number of 27 digits) contains 22 as substring.

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 80 ways as a sum of consecutive naturals, for example, 4978482411 + ... + 4978486639.

Almost surely, 2^{21054011056225} is an apocalyptic number.

21054011056225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21054011056225 is the 4588465-th square number.

21054011056225 is the 2294233-rd centered octagonal number.

It is an amenable number.

21054011056225 is a deficient number, since it is larger than the sum of its proper divisors (10334005629176).

21054011056225 is an frugal number, since it uses more digits than its factorization.

21054011056225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8544 (or 4272 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 34.

The spelling of 21054011056225 in words is "twenty-one trillion, fifty-four billion, eleven million, fifty-six thousand, two hundred twenty-five".