538005721 has 16 divisors (see below), whose sum is σ = 596655360. Its totient is φ = 481029120.

The previous prime is 538005701. The next prime is 538005739. The reversal of 538005721 is 127500835.

It is not a de Polignac number, because 538005721 - 2¹¹ = 538003673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (538005701) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 253561 + ... + 255673.

It is an arithmetic number, because the mean of its divisors is an integer number (37290960).

Almost surely, 2^538005721 is an apocalyptic number.

It is an amenable number.

538005721 is a deficient number, since it is larger than the sum of its proper divisors (58649639).

538005721 is a wasteful number, since it uses less digits than its factorization.

538005721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2496.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 538005721 is about 23194.9503340706. The cubic root of 538005721 is about 813.3215842871.

The spelling of 538005721 in words is "five hundred thirty-eight million, five thousand, seven hundred twenty-one".