999993971 has 2 divisors, whose sum is σ = 999993972. Its totient is φ = 999993970.

The previous prime is 999993947. The next prime is 999994003. The reversal of 999993971 is 179399999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999993971 - 2¹⁸ = 999731827 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 999993898 and 999993907.

It is not a weakly prime, because it can be changed into another prime (999993901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499996985 + 499996986.

It is an arithmetic number, because the mean of its divisors is an integer number (499996986).

Almost surely, 2^999993971 is an apocalyptic number.

999993971 is a deficient number, since it is larger than the sum of its proper divisors (1).

999993971 is an equidigital number, since it uses as much as digits as its factorization.

999993971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11160261, while the sum is 65.

The square root of 999993971 is about 31622.6812746800. The cubic root of 999993971 is about 999.9979903293.

The spelling of 999993971 in words is "nine hundred ninety-nine million, nine hundred ninety-three thousand, nine hundred seventy-one".