20612645 has 8 divisors (see below), whose sum is σ = 25074456. Its totient is φ = 16263936.

The previous prime is 20612639. The next prime is 20612659. The reversal of 20612645 is 54621602.

It can be written as a sum of positive squares in 4 ways, for example, as 4104676 + 16507969 = 2026^2 + 4063^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20612645 - 2⁴ = 20612629 is a prime.

It is a super-2 number, since 2×20612645² = 849762267792050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27872 + ... + 28601.

It is an arithmetic number, because the mean of its divisors is an integer number (3134307).

Almost surely, 2^20612645 is an apocalyptic number.

It is an amenable number.

20612645 is a deficient number, since it is larger than the sum of its proper divisors (4461811).

20612645 is an equidigital number, since it uses as much as digits as its factorization.

20612645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56551.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 20612645 is about 4540.1150866470. The cubic root of 20612645 is about 274.1855572616.

The spelling of 20612645 in words is "twenty million, six hundred twelve thousand, six hundred forty-five".