531973921 has 2 divisors, whose sum is σ = 531973922. Its totient is φ = 531973920.

The previous prime is 531973909. The next prime is 531973927. The reversal of 531973921 is 129379135.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 531533025 + 440896 = 23055^2 + 664^2 .

It is a cyclic number.

It is not a de Polignac number, because 531973921 - 2⁵ = 531973889 is a prime.

It is a super-2 number, since 2×531973921² = 565992505248228482, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (531973927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265986960 + 265986961.

It is an arithmetic number, because the mean of its divisors is an integer number (265986961).

Almost surely, 2^531973921 is an apocalyptic number.

It is an amenable number.

531973921 is a deficient number, since it is larger than the sum of its proper divisors (1).

531973921 is an equidigital number, since it uses as much as digits as its factorization.

531973921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51030, while the sum is 40.

The square root of 531973921 is about 23064.5598483908. The cubic root of 531973921 is about 810.2706614663.

The spelling of 531973921 in words is "five hundred thirty-one million, nine hundred seventy-three thousand, nine hundred twenty-one".