511721947 has 48 divisors (see below), whose sum is σ = 625121280. Its totient is φ = 416782080.

The previous prime is 511721923. The next prime is 511721971. The reversal of 511721947 is 749127115.

It is an interprime number because it is at equal distance from previous prime (511721923) and next prime (511721971).

It is not a de Polignac number, because 511721947 - 2²⁷ = 377504219 is a prime.

It is not an unprimeable number, because it can be changed into a prime (511721047) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6477454 + ... + 6477532.

It is an arithmetic number, because the mean of its divisors is an integer number (13023360).

Almost surely, 2^511721947 is an apocalyptic number.

511721947 is a deficient number, since it is larger than the sum of its proper divisors (113399333).

511721947 is a wasteful number, since it uses less digits than its factorization.

511721947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232 (or 221 counting only the distinct ones).

The product of its digits is 17640, while the sum is 37.

The square root of 511721947 is about 22621.2720022549. The cubic root of 511721947 is about 799.8551545055.

The spelling of 511721947 in words is "five hundred eleven million, seven hundred twenty-one thousand, nine hundred forty-seven".