1990308121 has 16 divisors (see below), whose sum is σ = 2120408640. Its totient is φ = 1862827200.

The previous prime is 1990308119. The next prime is 1990308127. The reversal of 1990308121 is 1218030991.

It is a cyclic number.

It is not a de Polignac number, because 1990308121 - 2¹ = 1990308119 is a prime.

It is a super-2 number, since 2×1990308121² = 7922652833037101282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1990308127) 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, 1233111 + ... + 1234723.

It is an arithmetic number, because the mean of its divisors is an integer number (132525540).

Almost surely, 2^1990308121 is an apocalyptic number.

It is an amenable number.

1990308121 is a deficient number, since it is larger than the sum of its proper divisors (130100519).

1990308121 is a wasteful number, since it uses less digits than its factorization.

1990308121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2376.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 1990308121 is about 44612.8694549006. The cubic root of 1990308121 is about 1257.8825865228.

The spelling of 1990308121 in words is "one billion, nine hundred ninety million, three hundred eight thousand, one hundred twenty-one".