20994769820025 has 81 divisors (see below), whose sum is σ = 37785426962413. Its totient is φ = 11143436160000.

The previous prime is 20994769820023. The next prime is 20994769820039. The reversal of 20994769820025 is 52002896749902.

The square root of 20994769820025 is 4582005.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1946887205481 + 19047882614544 = 1395309^2 + 4364388^2 .

It is not a de Polignac number, because 20994769820025 - 2¹ = 20994769820023 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20994769820023) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 17251248217 + ... + 17251249433.

Almost surely, 2^{20994769820025} is an apocalyptic number.

20994769820025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20994769820025 is the 4582005-th square number.

20994769820025 is the 2291003-rd centered octagonal number.

It is an amenable number.

20994769820025 is a deficient number, since it is larger than the sum of its proper divisors (16790657142388).

20994769820025 is an frugal number, since it uses more digits than its factorization.

20994769820025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2952 (or 1476 counting only the distinct ones).

The product of its (nonzero) digits is 39191040, while the sum is 63.

The spelling of 20994769820025 in words is "twenty trillion, nine hundred ninety-four billion, seven hundred sixty-nine million, eight hundred twenty thousand, twenty-five".