2151578946 has 48 divisors (see below), whose sum is σ = 4773117024. Its totient is φ = 641232000.

The previous prime is 2151578927. The next prime is 2151579061. The reversal of 2151578946 is 6498751512.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 2151578895 and 2151578904.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 241206 + ... + 249966.

It is an arithmetic number, because the mean of its divisors is an integer number (99439938).

Almost surely, 2^2151578946 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2151578946, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2386558512).

2151578946 is an abundant number, since it is smaller than the sum of its proper divisors (2621538078).

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

2151578946 is a wasteful number, since it uses less digits than its factorization.

2151578946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8899 (or 8838 counting only the distinct ones).

The product of its digits is 604800, while the sum is 48.

The square root of 2151578946 is about 46385.1155652328. The cubic root of 2151578946 is about 1290.9787548331.

The spelling of 2151578946 in words is "two billion, one hundred fifty-one million, five hundred seventy-eight thousand, nine hundred forty-six".