2161261542 has 32 divisors (see below), whose sum is σ = 4759565184. Its totient is φ = 648804800.

The previous prime is 2161261519. The next prime is 2161261567. The reversal of 2161261542 is 2451621612.

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, 145959 + ... + 160082.

It is an arithmetic number, because the mean of its divisors is an integer number (148736412).

Almost surely, 2^2161261542 is an apocalyptic number.

2161261542 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

2161261542 is an abundant number, since it is smaller than the sum of its proper divisors (2598303642).

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

2161261542 is a wasteful number, since it uses less digits than its factorization.

2161261542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306164.

The product of its digits is 5760, while the sum is 30.

The square root of 2161261542 is about 46489.3702043811. The cubic root of 2161261542 is about 1292.9124233608.

The spelling of 2161261542 in words is "two billion, one hundred sixty-one million, two hundred sixty-one thousand, five hundred forty-two".