1620465555 has 16 divisors (see below), whose sum is σ = 2593476864. Its totient is φ = 864004320.

The previous prime is 1620465547. The next prime is 1620465563. The reversal of 1620465555 is 5555640261.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1620465547) and next prime (1620465563).

It is not a de Polignac number, because 1620465555 - 2³ = 1620465547 is a prime.

It is a super-2 number, since 2×1620465555² = 5251817229882916050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48162 + ... + 74568.

It is an arithmetic number, because the mean of its divisors is an integer number (162092304).

Almost surely, 2^1620465555 is an apocalyptic number.

1620465555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1620465555 is a deficient number, since it is larger than the sum of its proper divisors (973011309).

1620465555 is a wasteful number, since it uses less digits than its factorization.

1620465555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30506.

The product of its (nonzero) digits is 180000, while the sum is 39.

The square root of 1620465555 is about 40255.0065830326. The cubic root of 1620465555 is about 1174.5727868964.

The spelling of 1620465555 in words is "one billion, six hundred twenty million, four hundred sixty-five thousand, five hundred fifty-five".