20505554 has 8 divisors (see below), whose sum is σ = 31179900. Its totient is φ = 10112256.

The previous prime is 20505497. The next prime is 20505571. The reversal of 20505554 is 45550502.

It can be written as a sum of positive squares in 2 ways, for example, as 20475625 + 29929 = 4525^2 + 173^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 70079 + ... + 70370.

Almost surely, 2^20505554 is an apocalyptic number.

20505554 is a deficient number, since it is larger than the sum of its proper divisors (10674346).

20505554 is a wasteful number, since it uses less digits than its factorization.

20505554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140524.

The product of its (nonzero) digits is 5000, while the sum is 26.

The square root of 20505554 is about 4528.3058642278. The cubic root of 20505554 is about 273.7098977278.

The spelling of 20505554 in words is "twenty million, five hundred five thousand, five hundred fifty-four".