651247222121 has 4 divisors (see below), whose sum is σ = 651250620372. Its totient is φ = 651243823872.

The previous prime is 651247222103. The next prime is 651247222133. The reversal of 651247222121 is 121222742156.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 160636632025 + 490610590096 = 400795^2 + 700436^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-651247222121 is a prime.

It is a super-2 number, since 2×651247222121² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (651247222721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1393316 + ... + 1801061.

It is an arithmetic number, because the mean of its divisors is an integer number (162812655093).

Almost surely, 2^651247222121 is an apocalyptic number.

It is an amenable number.

651247222121 is a deficient number, since it is larger than the sum of its proper divisors (3398251).

651247222121 is a wasteful number, since it uses less digits than its factorization.

651247222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3398250.

The product of its digits is 26880, while the sum is 35.

Adding to 651247222121 its reverse (121222742156), we get a palindrome (772469964277).

The spelling of 651247222121 in words is "six hundred fifty-one billion, two hundred forty-seven million, two hundred twenty-two thousand, one hundred twenty-one".