1023865921 has 8 divisors (see below), whose sum is σ = 1107572480. Its totient is φ = 940866192.

The previous prime is 1023865891. The next prime is 1023865951. The reversal of 1023865921 is 1295683201.

It is an interprime number because it is at equal distance from previous prime (1023865891) and next prime (1023865951).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1023865921 - 2²⁹ = 486995009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1023865951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 173691 + ... + 179488.

It is an arithmetic number, because the mean of its divisors is an integer number (138446560).

Almost surely, 2^1023865921 is an apocalyptic number.

It is an amenable number.

1023865921 is a deficient number, since it is larger than the sum of its proper divisors (83706559).

1023865921 is a wasteful number, since it uses less digits than its factorization.

1023865921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353415.

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 1023865921 is about 31997.9049470430. The cubic root of 1023865921 is about 1007.8928460805.

The spelling of 1023865921 in words is "one billion, twenty-three million, eight hundred sixty-five thousand, nine hundred twenty-one".