9921701790 has 288 divisors, whose sum is σ = 35256495456. Its totient is φ = 1902942720.

The previous prime is 9921701761. The next prime is 9921701819. The reversal of 9921701790 is 971071299.

It is an interprime number because it is at equal distance from previous prime (9921701761) and next prime (9921701819).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 622764 + ... + 638496.

It is an arithmetic number, because the mean of its divisors is an integer number (122418387).

Almost surely, 2^9921701790 is an apocalyptic number.

9921701790 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 9921701790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17628247728).

9921701790 is an abundant number, since it is smaller than the sum of its proper divisors (25334793666).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9921701790 is a wasteful number, since it uses less digits than its factorization.

9921701790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15784 (or 15774 counting only the distinct ones).

The product of its (nonzero) digits is 71442, while the sum is 45.

The square root of 9921701790 is about 99607.7396089280. The cubic root of 9921701790 is about 2148.7970043130.

The spelling of 9921701790 in words is "nine billion, nine hundred twenty-one million, seven hundred one thousand, seven hundred ninety".