20927990 has 8 divisors (see below), whose sum is σ = 37670400. Its totient is φ = 8371192.

The previous prime is 20927981. The next prime is 20927993. The reversal of 20927990 is 9972902.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20927993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1046390 + ... + 1046409.

It is an arithmetic number, because the mean of its divisors is an integer number (4708800).

Almost surely, 2^20927990 is an apocalyptic number.

20927990 is a deficient number, since it is larger than the sum of its proper divisors (16742410).

20927990 is a wasteful number, since it uses less digits than its factorization.

20927990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2092806.

The product of its (nonzero) digits is 20412, while the sum is 38.

The square root of 20927990 is about 4574.7120127938. The cubic root of 20927990 is about 275.5767070879.

It can be divided in two parts, 209 and 27990, that multiplied together give a triangular number (5849910 = T₃₄₂₀).

The spelling of 20927990 in words is "twenty million, nine hundred twenty-seven thousand, nine hundred ninety".