20645051 has 8 divisors (see below), whose sum is σ = 23683584. Its totient is φ = 17628840.

The previous prime is 20645047. The next prime is 20645069. The reversal of 20645051 is 15054602.

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

It is a cyclic number.

It is not a de Polignac number, because 20645051 - 2² = 20645047 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20645551) 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 7 ways as a sum of consecutive naturals, for example, 3545 + ... + 7338.

It is an arithmetic number, because the mean of its divisors is an integer number (2960448).

Almost surely, 2^20645051 is an apocalyptic number.

20645051 is a deficient number, since it is larger than the sum of its proper divisors (3038533).

20645051 is a wasteful number, since it uses less digits than its factorization.

20645051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11161.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 20645051 is about 4543.6825373259. The cubic root of 20645051 is about 274.3291682172.

Adding to 20645051 its reverse (15054602), we get a palindrome (35699653).

The spelling of 20645051 in words is "twenty million, six hundred forty-five thousand, fifty-one".