1662291998 has 4 divisors (see below), whose sum is σ = 2493438000. Its totient is φ = 831145998.

The previous prime is 1662291997. The next prime is 1662292003. The reversal of 1662291998 is 8991922661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8991922661 = 131 ⋅68640631.

It is a super-2 number, since 2×1662291998² = 5526429373229664008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1662291997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 415572998 + ... + 415573001.

It is an arithmetic number, because the mean of its divisors is an integer number (623359500).

Almost surely, 2^1662291998 is an apocalyptic number.

1662291998 is a deficient number, since it is larger than the sum of its proper divisors (831146002).

1662291998 is an equidigital number, since it uses as much as digits as its factorization.

1662291998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 831146001.

The product of its digits is 839808, while the sum is 53.

The square root of 1662291998 is about 40771.2153117858. The cubic root of 1662291998 is about 1184.5928439136.

The spelling of 1662291998 in words is "one billion, six hundred sixty-two million, two hundred ninety-one thousand, nine hundred ninety-eight".