721442 has 8 divisors (see below), whose sum is σ = 1090476. Its totient is φ = 357952.

The previous prime is 721439. The next prime is 721451. The reversal of 721442 is 244127.

It can be written as a sum of positive squares in 2 ways, for example, as 707281 + 14161 = 841^2 + 119^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1043 + ... + 1590.

2⁷²¹⁴⁴² is an apocalyptic number.

721442 is a deficient number, since it is larger than the sum of its proper divisors (369034).

721442 is a wasteful number, since it uses less digits than its factorization.

721442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2772.

The product of its digits is 448, while the sum is 20.

The square root of 721442 is about 849.3774190547. The cubic root of 721442 is about 89.6878900824.

Adding to 721442 its reverse (244127), we get a palindrome (965569).

The spelling of 721442 in words is "seven hundred twenty-one thousand, four hundred forty-two", and thus it is an iban number.