9951122021 has 4 divisors (see below), whose sum is σ = 9951509100. Its totient is φ = 9950734944.

The previous prime is 9951121979. The next prime is 9951122033. The reversal of 9951122021 is 1202211599.

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 334377796 + 9616744225 = 18286^2 + 98065^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9951122021 is a prime.

It is a super-2 number, since 2×9951122021² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9951122521) 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, 152006 + ... + 207383.

It is an arithmetic number, because the mean of its divisors is an integer number (2487877275).

Almost surely, 2^9951122021 is an apocalyptic number.

It is an amenable number.

9951122021 is a deficient number, since it is larger than the sum of its proper divisors (387079).

9951122021 is a wasteful number, since it uses less digits than its factorization.

9951122021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 387078.

The product of its (nonzero) digits is 3240, while the sum is 32.

The square root of 9951122021 is about 99755.3107408322. The cubic root of 9951122021 is about 2150.9188083705.

The spelling of 9951122021 in words is "nine billion, nine hundred fifty-one million, one hundred twenty-two thousand, twenty-one".