1057321221 has 16 divisors (see below), whose sum is σ = 1566941760. Its totient is φ = 628709120.

The previous prime is 1057321219. The next prime is 1057321267. The reversal of 1057321221 is 1221237501.

It is a cyclic number.

It is not a de Polignac number, because 1057321221 - 2¹ = 1057321219 is a prime.

It is a super-2 number, since 2×1057321221² = 2235856328753861682, which contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1057321191 and 1057321200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1057321621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 300516 + ... + 304013.

It is an arithmetic number, because the mean of its divisors is an integer number (97933860).

Almost surely, 2^1057321221 is an apocalyptic number.

1057321221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1057321221 is a deficient number, since it is larger than the sum of its proper divisors (509620539).

1057321221 is a wasteful number, since it uses less digits than its factorization.

1057321221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604596.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 1057321221 is about 32516.4761467168. The cubic root of 1057321221 is about 1018.7531930295.

Adding to 1057321221 its reverse (1221237501), we get a palindrome (2278558722).

It can be divided in two parts, 105732 and 1221, that added together give a triangular number (106953 = T₄₆₂).

The spelling of 1057321221 in words is "one billion, fifty-seven million, three hundred twenty-one thousand, two hundred twenty-one".