648769681 has 8 divisors (see below), whose sum is σ = 758694464. Its totient is φ = 543155760.

The previous prime is 648769679. The next prime is 648769699. The reversal of 648769681 is 186967846.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 648769681 - 2¹ = 648769679 is a prime.

It is a super-2 number, since 2×648769681² = 841804197969683522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (648769601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1077390 + ... + 1077991.

It is an arithmetic number, because the mean of its divisors is an integer number (94836808).

Almost surely, 2^648769681 is an apocalyptic number.

It is an amenable number.

648769681 is a deficient number, since it is larger than the sum of its proper divisors (109924783).

648769681 is a wasteful number, since it uses less digits than its factorization.

648769681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2155431.

The product of its digits is 3483648, while the sum is 55.

The square root of 648769681 is about 25470.9575988026. The cubic root of 648769681 is about 865.6922214667.

The spelling of 648769681 in words is "six hundred forty-eight million, seven hundred sixty-nine thousand, six hundred eighty-one".