1357213981 has 2 divisors, whose sum is σ = 1357213982. Its totient is φ = 1357213980.

The previous prime is 1357213943. The next prime is 1357213999. The reversal of 1357213981 is 1893127531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1098325881 + 258888100 = 33141^2 + 16090^2 .

It is a cyclic number.

It is not a de Polignac number, because 1357213981 - 2¹³ = 1357205789 is a prime.

It is a super-2 number, since 2×1357213981² = 3684059580443736722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1357213901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 678606990 + 678606991.

It is an arithmetic number, because the mean of its divisors is an integer number (678606991).

Almost surely, 2^1357213981 is an apocalyptic number.

It is an amenable number.

1357213981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1357213981 is an equidigital number, since it uses as much as digits as its factorization.

1357213981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 40.

The square root of 1357213981 is about 36840.3851907116. The cubic root of 1357213981 is about 1107.1745854704.

The spelling of 1357213981 in words is "one billion, three hundred fifty-seven million, two hundred thirteen thousand, nine hundred eighty-one".