20415499457 has 2 divisors, whose sum is σ = 20415499458. Its totient is φ = 20415499456.

The previous prime is 20415499439. The next prime is 20415499471. The reversal of 20415499457 is 75499451402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19858728241 + 556771216 = 140921^2 + 23596^2 .

It is a cyclic number.

It is not a de Polignac number, because 20415499457 - 2²⁸ = 20147064001 is a prime.

It is not a weakly prime, because it can be changed into another prime (20415499057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10207749728 + 10207749729.

It is an arithmetic number, because the mean of its divisors is an integer number (10207749729).

Almost surely, 2^20415499457 is an apocalyptic number.

It is an amenable number.

20415499457 is a deficient number, since it is larger than the sum of its proper divisors (1).

20415499457 is an equidigital number, since it uses as much as digits as its factorization.

20415499457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1814400, while the sum is 50.

The spelling of 20415499457 in words is "twenty billion, four hundred fifteen million, four hundred ninety-nine thousand, four hundred fifty-seven".