511821972 has 36 divisors (see below), whose sum is σ = 1294520500. Its totient is φ = 170508672.

The previous prime is 511821971. The next prime is 511821977. The reversal of 511821972 is 279128115.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 156650256 + 355171716 = 12516^2 + 18846^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-3 number, since 3×511821972³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (511821971) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 86154 + ... + 91902.

Almost surely, 2^511821972 is an apocalyptic number.

It is an amenable number.

511821972 is an abundant number, since it is smaller than the sum of its proper divisors (782698528).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

511821972 is a wasteful number, since it uses less digits than its factorization.

511821972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8232 (or 8227 counting only the distinct ones).

The product of its digits is 10080, while the sum is 36.

The square root of 511821972 is about 22623.4827557562. The cubic root of 511821972 is about 799.9072663343.

The spelling of 511821972 in words is "five hundred eleven million, eight hundred twenty-one thousand, nine hundred seventy-two".