1621906 has 32 divisors (see below), whose sum is σ = 2939328. Its totient is φ = 661440.

The previous prime is 1621877. The next prime is 1621909. The reversal of 1621906 is 6091261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15105 + ... + 15211.

It is an arithmetic number, because the mean of its divisors is an integer number (91854).

2^1621906 is an apocalyptic number.

1621906 is a deficient number, since it is larger than the sum of its proper divisors (1317422).

1621906 is a wasteful number, since it uses less digits than its factorization.

1621906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 1621906 is about 1273.5407335457. The cubic root of 1621906 is about 117.4920712924.

The spelling of 1621906 in words is "one million, six hundred twenty-one thousand, nine hundred six".