1989406457 has 8 divisors (see below), whose sum is σ = 2098605600. Its totient is φ = 1880656704.

The previous prime is 1989406421. The next prime is 1989406477. The reversal of 1989406457 is 7546049891.

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 1989406457 - 2¹⁶ = 1989340921 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1989406399 and 1989406408.

It is not an unprimeable number, because it can be changed into a prime (1989406477) 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, 103232 + ... + 120977.

It is an arithmetic number, because the mean of its divisors is an integer number (262325700).

Almost surely, 2^1989406457 is an apocalyptic number.

It is an amenable number.

1989406457 is a deficient number, since it is larger than the sum of its proper divisors (109199143).

1989406457 is a wasteful number, since it uses less digits than its factorization.

1989406457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224695.

The product of its (nonzero) digits is 2177280, while the sum is 53.

The square root of 1989406457 is about 44602.7628852743. The cubic root of 1989406457 is about 1257.6926060958.

The spelling of 1989406457 in words is "one billion, nine hundred eighty-nine million, four hundred six thousand, four hundred fifty-seven".