10209221861 has 4 divisors (see below), whose sum is σ = 10266256800. Its totient is φ = 10152186924.

The previous prime is 10209221819. The next prime is 10209221917. The reversal of 10209221861 is 16812290201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10209221861 is a prime.

It is a super-2 number, since 2×10209221861² (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 (10209223861) 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, 28517201 + ... + 28517558.

It is an arithmetic number, because the mean of its divisors is an integer number (2566564200).

Almost surely, 2^10209221861 is an apocalyptic number.

It is an amenable number.

10209221861 is a deficient number, since it is larger than the sum of its proper divisors (57034939).

10209221861 is an equidigital number, since it uses as much as digits as its factorization.

10209221861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57034938.

The product of its (nonzero) digits is 3456, while the sum is 32.

The spelling of 10209221861 in words is "ten billion, two hundred nine million, two hundred twenty-one thousand, eight hundred sixty-one".