721954 has 4 divisors (see below), whose sum is σ = 1082934. Its totient is φ = 360976.

The previous prime is 721951. The next prime is 721961. The reversal of 721954 is 459127.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 683929 + 38025 = 827^2 + 195^2 .

It is not an unprimeable number, because it can be changed into a prime (721951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180487 + ... + 180490.

2⁷²¹⁹⁵⁴ is an apocalyptic number.

721954 is a deficient number, since it is larger than the sum of its proper divisors (360980).

721954 is a wasteful number, since it uses less digits than its factorization.

721954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360979.

The product of its digits is 2520, while the sum is 28.

The square root of 721954 is about 849.6787628275. The cubic root of 721954 is about 89.7091019243.

The spelling of 721954 in words is "seven hundred twenty-one thousand, nine hundred fifty-four".