19771472537 has 2 divisors, whose sum is σ = 19771472538. Its totient is φ = 19771472536.

The previous prime is 19771472527. The next prime is 19771472573. The reversal of 19771472537 is 73527417791.

Together with next prime (19771472573) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18956883856 + 814588681 = 137684^2 + 28541^2 .

It is a cyclic number.

It is not a de Polignac number, because 19771472537 - 2⁴ = 19771472521 is a prime.

It is a super-2 number, since 2×19771472537² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (19771472507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9885736268 + 9885736269.

It is an arithmetic number, because the mean of its divisors is an integer number (9885736269).

Almost surely, 2^19771472537 is an apocalyptic number.

It is an amenable number.

19771472537 is a deficient number, since it is larger than the sum of its proper divisors (1).

19771472537 is an equidigital number, since it uses as much as digits as its factorization.

19771472537 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2593080, while the sum is 53.

The spelling of 19771472537 in words is "nineteen billion, seven hundred seventy-one million, four hundred seventy-two thousand, five hundred thirty-seven".