140161921 has 3 divisors (see below), whose sum is σ = 140173761. Its totient is φ = 140150082.

The previous prime is 140161913. The next prime is 140161933. The reversal of 140161921 is 129161041.

The square root of 140161921 is 11839.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 140161921 - 2³ = 140161913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (140161951) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 5920 + ... + 17758.

It is an arithmetic number, because the mean of its divisors is an integer number (46724587).

Almost surely, 2^140161921 is an apocalyptic number.

140161921 is the 11839-th square number.

140161921 is the 5920-th centered octagonal number.

It is an amenable number.

140161921 is a deficient number, since it is larger than the sum of its proper divisors (11840).

140161921 is an frugal number, since it uses more digits than its factorization.

140161921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23678 (or 11839 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 25.

The cubic root of 140161921 is about 519.4495173054.

Multiplying 140161921 by its sum of digits (25), we get a square (3504048025 = 59195²).

The spelling of 140161921 in words is "one hundred forty million, one hundred sixty-one thousand, nine hundred twenty-one".