21316034947 has 2 divisors, whose sum is σ = 21316034948. Its totient is φ = 21316034946.

The previous prime is 21316034939. The next prime is 21316034959. The reversal of 21316034947 is 74943061312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21316034947 - 2³ = 21316034939 is a prime.

It is not a weakly prime, because it can be changed into another prime (21316034917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10658017473 + 10658017474.

It is an arithmetic number, because the mean of its divisors is an integer number (10658017474).

Almost surely, 2^21316034947 is an apocalyptic number.

21316034947 is a deficient number, since it is larger than the sum of its proper divisors (1).

21316034947 is an equidigital number, since it uses as much as digits as its factorization.

21316034947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 40.

The spelling of 21316034947 in words is "twenty-one billion, three hundred sixteen million, thirty-four thousand, nine hundred forty-seven".