648769261 has 6 divisors (see below), whose sum is σ = 754690830. Its totient is φ = 556087896.

The previous prime is 648769259. The next prime is 648769279. The reversal of 648769261 is 162967846.

It can be written as a sum of positive squares in only one way, i.e., 346183236 + 302586025 = 18606^2 + 17395^2 .

It is not a de Polignac number, because 648769261 - 2¹ = 648769259 is a prime.

It is a super-2 number, since 2×648769261² = 841803108036972242, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49), and also a Moran number because the ratio is a prime number: 13240189 = 648769261 / (6 + 4 + 8 + 7 + 6 + 9 + 2 + 6 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648769291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6620046 + ... + 6620143.

It is an arithmetic number, because the mean of its divisors is an integer number (125781805).

Almost surely, 2^648769261 is an apocalyptic number.

It is an amenable number.

648769261 is a deficient number, since it is larger than the sum of its proper divisors (105921569).

648769261 is a wasteful number, since it uses less digits than its factorization.

648769261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13240203 (or 13240196 counting only the distinct ones).

The product of its digits is 870912, while the sum is 49.

The square root of 648769261 is about 25470.9493541171. The cubic root of 648769261 is about 865.6920346563.

The spelling of 648769261 in words is "six hundred forty-eight million, seven hundred sixty-nine thousand, two hundred sixty-one".