20540737647 has 8 divisors (see below), whose sum is σ = 30430722480. Its totient is φ = 13693825080.

The previous prime is 20540737603. The next prime is 20540737699. The reversal of 20540737647 is 74673704502.

20540737647 is a `hidden beast` number, since 205 + 407 + 37 + 6 + 4 + 7 = 666.

It is not a de Polignac number, because 20540737647 - 2¹⁴ = 20540721263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20540737447) 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, 380384004 + ... + 380384057.

It is an arithmetic number, because the mean of its divisors is an integer number (3803840310).

Almost surely, 2^20540737647 is an apocalyptic number.

20540737647 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

20540737647 is a deficient number, since it is larger than the sum of its proper divisors (9889984833).

20540737647 is an equidigital number, since it uses as much as digits as its factorization.

20540737647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 760768070 (or 760768064 counting only the distinct ones).

The product of its (nonzero) digits is 987840, while the sum is 45.

The spelling of 20540737647 in words is "twenty billion, five hundred forty million, seven hundred thirty-seven thousand, six hundred forty-seven".