20553690 has 16 divisors (see below), whose sum is σ = 49328928. Its totient is φ = 5480976.

The previous prime is 20553647. The next prime is 20553691. The reversal of 20553690 is 9635502.

It is a super-2 number, since 2×20553690² = 844908345232200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 685123 = 20553690 / (2 + 0 + 5 + 5 + 3 + 6 + 9 + 0).

It is not an unprimeable number, because it can be changed into a prime (20553691) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 342532 + ... + 342591.

It is an arithmetic number, because the mean of its divisors is an integer number (3083058).

Almost surely, 2^20553690 is an apocalyptic number.

20553690 is an abundant number, since it is smaller than the sum of its proper divisors (28775238).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20553690 is a wasteful number, since it uses less digits than its factorization.

20553690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 685133.

The product of its (nonzero) digits is 8100, while the sum is 30.

The square root of 20553690 is about 4533.6177606852. The cubic root of 20553690 is about 273.9239048461.

The spelling of 20553690 in words is "twenty million, five hundred fifty-three thousand, six hundred ninety".