1051205721 has 8 divisors (see below), whose sum is σ = 1407893760. Its totient is φ = 697660752.

The previous prime is 1051205711. The next prime is 1051205737. The reversal of 1051205721 is 1275021501.

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

It is not a de Polignac number, because 1051205721 - 2⁵ = 1051205689 is a prime.

It is a super-2 number, since 2×1051205721² = 2210066935726259682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1051205691 and 1051205700.

It is not an unprimeable number, because it can be changed into a prime (1051205711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 784986 + ... + 786323.

It is an arithmetic number, because the mean of its divisors is an integer number (175986720).

Almost surely, 2^1051205721 is an apocalyptic number.

It is an amenable number.

1051205721 is a deficient number, since it is larger than the sum of its proper divisors (356688039).

1051205721 is a wasteful number, since it uses less digits than its factorization.

1051205721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571535.

The product of its (nonzero) digits is 700, while the sum is 24.

The square root of 1051205721 is about 32422.3028330808. The cubic root of 1051205721 is about 1016.7852525772.

The spelling of 1051205721 in words is "one billion, fifty-one million, two hundred five thousand, seven hundred twenty-one".