20404017661655 has 8 divisors (see below), whose sum is σ = 24484848242784. Its totient is φ = 16323196096800.

The previous prime is 20404017661639. The next prime is 20404017661667. The reversal of 20404017661655 is 55616671040402.

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

It is not a de Polignac number, because 20404017661655 - 2⁴ = 20404017661639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4643270 + ... + 7897340.

It is an arithmetic number, because the mean of its divisors is an integer number (3060606030348).

Almost surely, 2^{20404017661655} is an apocalyptic number.

20404017661655 is a deficient number, since it is larger than the sum of its proper divisors (4080830581129).

20404017661655 is a wasteful number, since it uses less digits than its factorization.

20404017661655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4508137.

The product of its (nonzero) digits is 1209600, while the sum is 47.

The spelling of 20404017661655 in words is "twenty trillion, four hundred four billion, seventeen million, six hundred sixty-one thousand, six hundred fifty-five".