201978493 has 8 divisors (see below), whose sum is σ = 213062400. Its totient is φ = 190939968.

The previous prime is 201978473. The next prime is 201978509. The reversal of 201978493 is 394879102.

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

It is not a de Polignac number, because 201978493 - 2⁵ = 201978461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201978463) 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, 1996 + ... + 20197.

It is an arithmetic number, because the mean of its divisors is an integer number (26632800).

Almost surely, 2^201978493 is an apocalyptic number.

It is an amenable number.

201978493 is a deficient number, since it is larger than the sum of its proper divisors (11083907).

201978493 is a wasteful number, since it uses less digits than its factorization.

201978493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22691.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 201978493 is about 14211.9137697919. The cubic root of 201978493 is about 586.7256064163.

The spelling of 201978493 in words is "two hundred one million, nine hundred seventy-eight thousand, four hundred ninety-three".