1620156855 has 16 divisors (see below), whose sum is σ = 2592754560. Its totient is φ = 863915808.

The previous prime is 1620156821. The next prime is 1620156887. The reversal of 1620156855 is 5586510261.

It is not a de Polignac number, because 1620156855 - 2¹⁴ = 1620140471 is a prime.

It is a congruent number.

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, 129924 + ... + 141846.

It is an arithmetic number, because the mean of its divisors is an integer number (162047160).

Almost surely, 2^1620156855 is an apocalyptic number.

1620156855 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1620156855 is a deficient number, since it is larger than the sum of its proper divisors (972597705).

1620156855 is a wasteful number, since it uses less digits than its factorization.

1620156855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20990.

The product of its (nonzero) digits is 72000, while the sum is 39.

The square root of 1620156855 is about 40251.1720947353. The cubic root of 1620156855 is about 1174.4981964708.

The spelling of 1620156855 in words is "one billion, six hundred twenty million, one hundred fifty-six thousand, eight hundred fifty-five".