1971421 has 12 divisors (see below), whose sum is σ = 2145792. Its totient is φ = 1809864.

The previous prime is 1971401. The next prime is 1971427. The reversal of 1971421 is 1241791.

It is a de Polignac number, because none of the positive numbers 2^k-1971421 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1971427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15460 + ... + 15586.

It is an arithmetic number, because the mean of its divisors is an integer number (178816).

2^1971421 is an apocalyptic number.

It is an amenable number.

1971421 is a deficient number, since it is larger than the sum of its proper divisors (174371).

1971421 is a wasteful number, since it uses less digits than its factorization.

1971421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208 (or 189 counting only the distinct ones).

The product of its digits is 504, while the sum is 25.

The square root of 1971421 is about 1404.0730038000. The cubic root of 1971421 is about 125.3891022057.

The spelling of 1971421 in words is "one million, nine hundred seventy-one thousand, four hundred twenty-one".