651121601 has 8 divisors (see below), whose sum is σ = 725387880. Its totient is φ = 580309632.

The previous prime is 651121577. The next prime is 651121633. The reversal of 651121601 is 106121156.

It can be written as a sum of positive squares in 4 ways, for example, as 9006001 + 642115600 = 3001^2 + 25340^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 651121601 - 2²² = 646927297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (651121501) 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, 863180 + ... + 863933.

It is an arithmetic number, because the mean of its divisors is an integer number (90673485).

Almost surely, 2^651121601 is an apocalyptic number.

It is an amenable number.

651121601 is a deficient number, since it is larger than the sum of its proper divisors (74266279).

651121601 is a wasteful number, since it uses less digits than its factorization.

651121601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1727155.

The product of its (nonzero) digits is 360, while the sum is 23.

The square root of 651121601 is about 25517.0844925513. The cubic root of 651121601 is about 866.7370624443.

Adding to 651121601 its reverse (106121156), we get a palindrome (757242757).

The spelling of 651121601 in words is "six hundred fifty-one million, one hundred twenty-one thousand, six hundred one".