20751520913 has 2 divisors, whose sum is σ = 20751520914. Its totient is φ = 20751520912.

The previous prime is 20751520861. The next prime is 20751520927. The reversal of 20751520913 is 31902515702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13892865424 + 6858655489 = 117868^2 + 82817^2 .

It is a cyclic number.

It is not a de Polignac number, because 20751520913 - 2¹² = 20751516817 is a prime.

It is not a weakly prime, because it can be changed into another prime (20751550913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10375760456 + 10375760457.

It is an arithmetic number, because the mean of its divisors is an integer number (10375760457).

Almost surely, 2^20751520913 is an apocalyptic number.

It is an amenable number.

20751520913 is a deficient number, since it is larger than the sum of its proper divisors (1).

20751520913 is an equidigital number, since it uses as much as digits as its factorization.

20751520913 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18900, while the sum is 35.

The spelling of 20751520913 in words is "twenty billion, seven hundred fifty-one million, five hundred twenty thousand, nine hundred thirteen".