1357981981 has 8 divisors (see below), whose sum is σ = 1438305984. Its totient is φ = 1277707200.

The previous prime is 1357981957. The next prime is 1357981993. The reversal of 1357981981 is 1891897531.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1357981981 - 2¹⁵ = 1357949213 is a prime.

It is a super-2 number, since 2×1357981981² = 3688230121441368722, which 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 (1357981181) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55096 + ... + 75838.

It is an arithmetic number, because the mean of its divisors is an integer number (179788248).

Almost surely, 2^1357981981 is an apocalyptic number.

It is an amenable number.

1357981981 is a deficient number, since it is larger than the sum of its proper divisors (80324003).

1357981981 is a wasteful number, since it uses less digits than its factorization.

1357981981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24611.

The product of its digits is 544320, while the sum is 52.

The square root of 1357981981 is about 36850.8070603616. The cubic root of 1357981981 is about 1107.3833832372.

The spelling of 1357981981 in words is "one billion, three hundred fifty-seven million, nine hundred eighty-one thousand, nine hundred eighty-one".