21400202947 has 2 divisors, whose sum is σ = 21400202948. Its totient is φ = 21400202946.

The previous prime is 21400202921. The next prime is 21400202963. The reversal of 21400202947 is 74920200412.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21400202947 is a prime.

It is not a weakly prime, because it can be changed into another prime (21400203947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10700101473 + 10700101474.

It is an arithmetic number, because the mean of its divisors is an integer number (10700101474).

Almost surely, 2^21400202947 is an apocalyptic number.

21400202947 is a deficient number, since it is larger than the sum of its proper divisors (1).

21400202947 is an equidigital number, since it uses as much as digits as its factorization.

21400202947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 31.

The spelling of 21400202947 in words is "twenty-one billion, four hundred million, two hundred two thousand, nine hundred forty-seven".