961423981 has 4 divisors (see below), whose sum is σ = 1098770272. Its totient is φ = 824077692.

The previous prime is 961423973. The next prime is 961423999. The reversal of 961423981 is 189324169.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 961423981 - 2³ = 961423973 is a prime.

It is a super-2 number, since 2×961423981² = 1848672142483776722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (961423961) 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, 68673135 + ... + 68673148.

It is an arithmetic number, because the mean of its divisors is an integer number (274692568).

Almost surely, 2^961423981 is an apocalyptic number.

It is an amenable number.

961423981 is a deficient number, since it is larger than the sum of its proper divisors (137346291).

961423981 is a wasteful number, since it uses less digits than its factorization.

961423981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137346290.

The product of its digits is 93312, while the sum is 43.

The square root of 961423981 is about 31006.8376491380. The cubic root of 961423981 is about 986.9723442015.

The spelling of 961423981 in words is "nine hundred sixty-one million, four hundred twenty-three thousand, nine hundred eighty-one".