1620836478 has 12 divisors (see below), whose sum is σ = 3511812408. Its totient is φ = 540278820.

The previous prime is 1620836471. The next prime is 1620836509. The reversal of 1620836478 is 8746380261.

1620836478 is a `hidden beast` number, since 16 + 208 + 364 + 78 = 666.

It is a super-2 number, since 2×1620836478² = 5254221776830888968, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620836471) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45023218 + ... + 45023253.

It is an arithmetic number, because the mean of its divisors is an integer number (292651034).

Almost surely, 2^1620836478 is an apocalyptic number.

1620836478 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1620836478 is an abundant number, since it is smaller than the sum of its proper divisors (1890975930).

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

1620836478 is a wasteful number, since it uses less digits than its factorization.

1620836478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90046479 (or 90046476 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 45.

The square root of 1620836478 is about 40259.6134854770. The cubic root of 1620836478 is about 1174.6623995847.

The spelling of 1620836478 in words is "one billion, six hundred twenty million, eight hundred thirty-six thousand, four hundred seventy-eight".