20553497 has 4 divisors (see below), whose sum is σ = 21635280. Its totient is φ = 19471716.

The previous prime is 20553479. The next prime is 20553499. The reversal of 20553497 is 79435502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20553497 - 2⁶ = 20553433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20553499) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 540863 + ... + 540900.

It is an arithmetic number, because the mean of its divisors is an integer number (5408820).

Almost surely, 2^20553497 is an apocalyptic number.

It is an amenable number.

20553497 is a deficient number, since it is larger than the sum of its proper divisors (1081783).

20553497 is a wasteful number, since it uses less digits than its factorization.

20553497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081782.

The product of its (nonzero) digits is 37800, while the sum is 35.

The square root of 20553497 is about 4533.5964752060. The cubic root of 20553497 is about 273.9230474578.

Adding to 20553497 its reverse (79435502), we get a palindrome (99988999).

The spelling of 20553497 in words is "twenty million, five hundred fifty-three thousand, four hundred ninety-seven".