1618477920 has 72 divisors (see below), whose sum is σ = 5523060816. Its totient is φ = 431593728.

The previous prime is 1618477919. The next prime is 1618477921. The reversal of 1618477920 is 297748161.

It is a happy number.

1618477920 is a `hidden beast` number, since 1 + 618 + 4 + 7 + 7 + 9 + 20 = 666.

It is an interprime number because it is at equal distance from previous prime (1618477919) and next prime (1618477921).

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1618477921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 560532 + ... + 563411.

It is an arithmetic number, because the mean of its divisors is an integer number (76709178).

Almost surely, 2^1618477920 is an apocalyptic number.

1618477920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1618477920 is an abundant number, since it is smaller than the sum of its proper divisors (3904582896).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1618477920 is a wasteful number, since it uses less digits than its factorization.

1618477920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1123964 (or 1123953 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 45.

The square root of 1618477920 is about 40230.3109607669. The cubic root of 1618477920 is about 1174.0923535294.

The spelling of 1618477920 in words is "one billion, six hundred eighteen million, four hundred seventy-seven thousand, nine hundred twenty".