726741561 has 32 divisors (see below), whose sum is σ = 1204455168. Its totient is φ = 379526400.

The previous prime is 726741559. The next prime is 726741593. The reversal of 726741561 is 165147627.

It is not a de Polignac number, because 726741561 - 2¹ = 726741559 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (726741541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14395 + ... + 40751.

It is an arithmetic number, because the mean of its divisors is an integer number (37639224).

Almost surely, 2^726741561 is an apocalyptic number.

It is an amenable number.

726741561 is a deficient number, since it is larger than the sum of its proper divisors (477713607).

726741561 is a wasteful number, since it uses less digits than its factorization.

726741561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26481.

The product of its digits is 70560, while the sum is 39.

The square root of 726741561 is about 26958.1446134559. The cubic root of 726741561 is about 899.0696398215.

It can be divided in two parts, 7267 and 41561, that added together give a triangular number (48828 = T₃₁₂).

The spelling of 726741561 in words is "seven hundred twenty-six million, seven hundred forty-one thousand, five hundred sixty-one".