21506734462139 has 2 divisors, whose sum is σ = 21506734462140. Its totient is φ = 21506734462138.

The previous prime is 21506734462019. The next prime is 21506734462151. The reversal of 21506734462139 is 93126443760512.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21506734462139 - 2¹² = 21506734458043 is a prime.

It is not a weakly prime, because it can be changed into another prime (21506734462439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10753367231069 + 10753367231070.

It is an arithmetic number, because the mean of its divisors is an integer number (10753367231070).

Almost surely, 2^{21506734462139} is an apocalyptic number.

21506734462139 is a deficient number, since it is larger than the sum of its proper divisors (1).

21506734462139 is an equidigital number, since it uses as much as digits as its factorization.

21506734462139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6531840, while the sum is 53.

The spelling of 21506734462139 in words is "twenty-one trillion, five hundred six billion, seven hundred thirty-four million, four hundred sixty-two thousand, one hundred thirty-nine".