721862164 has 6 divisors (see below), whose sum is σ = 1263258794. Its totient is φ = 360931080.

The previous prime is 721862161. The next prime is 721862191. The reversal of 721862164 is 461268127.

It can be written as a sum of positive squares in only one way, i.e., 600642064 + 121220100 = 24508^2 + 11010^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721862161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90232767 + ... + 90232774.

Almost surely, 2^721862164 is an apocalyptic number.

It is an amenable number.

721862164 is a deficient number, since it is larger than the sum of its proper divisors (541396630).

721862164 is a wasteful number, since it uses less digits than its factorization.

721862164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180465545 (or 180465543 counting only the distinct ones).

The product of its digits is 32256, while the sum is 37.

The square root of 721862164 is about 26867.4927002875. The cubic root of 721862164 is about 897.0529795411.

The spelling of 721862164 in words is "seven hundred twenty-one million, eight hundred sixty-two thousand, one hundred sixty-four".