1620157878 has 24 divisors (see below), whose sum is σ = 3511757808. Its totient is φ = 539834832.

The previous prime is 1620157859. The next prime is 1620157883. The reversal of 1620157878 is 8787510261.

It is a happy number.

1620157878 is a `hidden beast` number, since 1 + 6 + 2 + 0 + 1 + 578 + 78 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31375 + ... + 64997.

It is an arithmetic number, because the mean of its divisors is an integer number (146323242).

Almost surely, 2^1620157878 is an apocalyptic number.

1620157878 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1620157878 is an abundant number, since it is smaller than the sum of its proper divisors (1891599930).

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

1620157878 is a wasteful number, since it uses less digits than its factorization.

1620157878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36308 (or 36305 counting only the distinct ones).

The product of its (nonzero) digits is 188160, while the sum is 45.

The square root of 1620157878 is about 40251.1848024378. The cubic root of 1620157878 is about 1174.4984436714.

The spelling of 1620157878 in words is "one billion, six hundred twenty million, one hundred fifty-seven thousand, eight hundred seventy-eight".