1658999421 has 16 divisors (see below), whose sum is σ = 2587134400. Its totient is φ = 1047788784.

The previous prime is 1658999413. The next prime is 1658999423. The reversal of 1658999421 is 1249998561.

1658999421 is a `hidden beast` number, since 16 + 589 + 9 + 9 + 42 + 1 = 666.

It is not a de Polignac number, because 1658999421 - 2³ = 1658999413 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 (1658999423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1616446 + ... + 1617471.

It is an arithmetic number, because the mean of its divisors is an integer number (161695900).

Almost surely, 2^1658999421 is an apocalyptic number.

It is an amenable number.

1658999421 is a deficient number, since it is larger than the sum of its proper divisors (928134979).

1658999421 is a wasteful number, since it uses less digits than its factorization.

1658999421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3233945 (or 3233939 counting only the distinct ones).

The product of its digits is 1399680, while the sum is 54.

The square root of 1658999421 is about 40730.8166011928. The cubic root of 1658999421 is about 1183.8102013928.

The spelling of 1658999421 in words is "one billion, six hundred fifty-eight million, nine hundred ninety-nine thousand, four hundred twenty-one".