721536754 has 4 divisors (see below), whose sum is σ = 1082305134. Its totient is φ = 360768376.

The previous prime is 721536707. The next prime is 721536757. The reversal of 721536754 is 457635127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 457635127 = 19583 ⋅23369.

It can be written as a sum of positive squares in only one way, i.e., 496086529 + 225450225 = 22273^2 + 15015^2 .

It is not an unprimeable number, because it can be changed into a prime (721536757) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180384187 + ... + 180384190.

Almost surely, 2^721536754 is an apocalyptic number.

721536754 is a deficient number, since it is larger than the sum of its proper divisors (360768380).

721536754 is a wasteful number, since it uses less digits than its factorization.

721536754 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360768379.

The product of its digits is 176400, while the sum is 40.

The square root of 721536754 is about 26861.4361864737. The cubic root of 721536754 is about 896.9181643833.

The spelling of 721536754 in words is "seven hundred twenty-one million, five hundred thirty-six thousand, seven hundred fifty-four".