140001981 has 8 divisors (see below), whose sum is σ = 213336384. Its totient is φ = 80001120.

The previous prime is 140001973. The next prime is 140001997. The reversal of 140001981 is 189100041.

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

It is not a de Polignac number, because 140001981 - 2³ = 140001973 is a prime.

It is a super-2 number, since 2×140001981² = 39201109367848722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (140001941) 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, 3333360 + ... + 3333401.

It is an arithmetic number, because the mean of its divisors is an integer number (26667048).

Almost surely, 2^140001981 is an apocalyptic number.

It is an amenable number.

140001981 is a deficient number, since it is larger than the sum of its proper divisors (73334403).

140001981 is an equidigital number, since it uses as much as digits as its factorization.

140001981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6666771.

The product of its (nonzero) digits is 288, while the sum is 24.

The square root of 140001981 is about 11832.2432784320. The cubic root of 140001981 is about 519.2518592999.

The spelling of 140001981 in words is "one hundred forty million, one thousand, nine hundred eighty-one".