542721906 has 24 divisors (see below), whose sum is σ = 1245068604. Its totient is φ = 170265600.

The previous prime is 542721899. The next prime is 542721967. The reversal of 542721906 is 609127245.

542721906 is a `hidden beast` number, since 542 + 7 + 21 + 90 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 541260225 + 1461681 = 23265^2 + 1209^2 .

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 886495 + ... + 887106.

Almost surely, 2^542721906 is an apocalyptic number.

542721906 is an abundant number, since it is smaller than the sum of its proper divisors (702346698).

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

542721906 is a wasteful number, since it uses less digits than its factorization.

542721906 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1773626 (or 1773623 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 542721906 is about 23296.3925533547. The cubic root of 542721906 is about 815.6912128217.

The spelling of 542721906 in words is "five hundred forty-two million, seven hundred twenty-one thousand, nine hundred six".