20613893506 has 8 divisors (see below), whose sum is σ = 31987076220. Its totient is φ = 9951534768.

The previous prime is 20613893491. The next prime is 20613893537. The reversal of 20613893506 is 60539831602.

It can be written as a sum of positive squares in 2 ways, for example, as 18751194225 + 1862699281 = 136935^2 + 43159^2 .

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

It is a super-3 number, since 3×20613893506³ (a number of 32 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177705921 + ... + 177706036.

Almost surely, 2^20613893506 is an apocalyptic number.

20613893506 is a deficient number, since it is larger than the sum of its proper divisors (11373182714).

20613893506 is a wasteful number, since it uses less digits than its factorization.

20613893506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355411988.

The product of its (nonzero) digits is 233280, while the sum is 43.

The spelling of 20613893506 in words is "twenty billion, six hundred thirteen million, eight hundred ninety-three thousand, five hundred six".