20720611 has 2 divisors, whose sum is σ = 20720612. Its totient is φ = 20720610.

The previous prime is 20720599. The next prime is 20720633. The reversal of 20720611 is 11602702.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20720611 is a prime.

It is not a weakly prime, because it can be changed into another prime (20720681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10360305 + 10360306.

It is an arithmetic number, because the mean of its divisors is an integer number (10360306).

Almost surely, 2^20720611 is an apocalyptic number.

20720611 is a deficient number, since it is larger than the sum of its proper divisors (1).

20720611 is an equidigital number, since it uses as much as digits as its factorization.

20720611 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 20720611 is about 4551.9897846986. The cubic root of 20720611 is about 274.6634384014.

The spelling of 20720611 in words is "twenty million, seven hundred twenty thousand, six hundred eleven".