20654729 has 4 divisors (see below), whose sum is σ = 21741840. Its totient is φ = 19567620.

The previous prime is 20654701. The next prime is 20654747. The reversal of 20654729 is 92745602.

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, and also an emirpimes, since its reverse is a distinct semiprime: 92745602 = 2 ⋅46372801.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20654729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20654329) 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, 543527 + ... + 543564.

It is an arithmetic number, because the mean of its divisors is an integer number (5435460).

Almost surely, 2^20654729 is an apocalyptic number.

It is an amenable number.

20654729 is a deficient number, since it is larger than the sum of its proper divisors (1087111).

20654729 is a wasteful number, since it uses less digits than its factorization.

20654729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1087110.

The product of its (nonzero) digits is 30240, while the sum is 35.

The square root of 20654729 is about 4544.7474077225. The cubic root of 20654729 is about 274.3720282540.

The spelling of 20654729 in words is "twenty million, six hundred fifty-four thousand, seven hundred twenty-nine".