20520357 has 32 divisors (see below), whose sum is σ = 33202176. Its totient is φ = 11102400.

The previous prime is 20520337. The next prime is 20520389. The reversal of 20520357 is 75302502.

It is not a de Polignac number, because 20520357 - 2⁷ = 20520229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20520307) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 12528 + ... + 14070.

It is an arithmetic number, because the mean of its divisors is an integer number (1037568).

Almost surely, 2^20520357 is an apocalyptic number.

It is an amenable number.

20520357 is a deficient number, since it is larger than the sum of its proper divisors (12681819).

20520357 is a wasteful number, since it uses less digits than its factorization.

20520357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1601.

The product of its (nonzero) digits is 2100, while the sum is 24.

The square root of 20520357 is about 4529.9400658287. The cubic root of 20520357 is about 273.7757457907.

Adding to 20520357 its reverse (75302502), we get a palindrome (95822859).

The spelling of 20520357 in words is "twenty million, five hundred twenty thousand, three hundred fifty-seven".