20920747 has 8 divisors (see below), whose sum is σ = 21612096. Its totient is φ = 20238792.

The previous prime is 20920741. The next prime is 20920763. The reversal of 20920747 is 74702902.

It is a happy number.

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 20920747 - 2¹¹ = 20918699 is a prime.

It is a pancake number, because a pancake can be divided into 20920747 parts by 6468 straight cuts.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20920741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2328 + ... + 6874.

It is an arithmetic number, because the mean of its divisors is an integer number (2701512).

Almost surely, 2^20920747 is an apocalyptic number.

20920747 is a deficient number, since it is larger than the sum of its proper divisors (691349).

20920747 is a wasteful number, since it uses less digits than its factorization.

20920747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4697.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 20920747 is about 4573.9203097562. The cubic root of 20920747 is about 275.5449118319.

The spelling of 20920747 in words is "twenty million, nine hundred twenty thousand, seven hundred forty-seven".