1900420961 has 4 divisors (see below), whose sum is σ = 1904069124. Its totient is φ = 1896772800.

The previous prime is 1900420957. The next prime is 1900420969. The reversal of 1900420961 is 1690240091.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1690240091 = 971 ⋅1740721.

It can be written as a sum of positive squares in 2 ways, for example, as 901860961 + 998560000 = 30031^2 + 31600^2 .

It is a cyclic number.

It is not a de Polignac number, because 1900420961 - 2² = 1900420957 is a prime.

It is a super-2 number, since 2×1900420961² = 7223199658016327042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1900420969) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1823300 + ... + 1824341.

It is an arithmetic number, because the mean of its divisors is an integer number (476017281).

Almost surely, 2^1900420961 is an apocalyptic number.

It is an amenable number.

1900420961 is a deficient number, since it is larger than the sum of its proper divisors (3648163).

1900420961 is an equidigital number, since it uses as much as digits as its factorization.

1900420961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3648162.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 1900420961 is about 43593.8179218109. The cubic root of 1900420961 is about 1238.6537941803.

The spelling of 1900420961 in words is "one billion, nine hundred million, four hundred twenty thousand, nine hundred sixty-one".