65457990 has 128 divisors (see below), whose sum is σ = 199221120. Its totient is φ = 15151104.

The previous prime is 65457971. The next prime is 65457991. The reversal of 65457990 is 9975456.

It is a happy number.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65457991) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 59122 + ... + 60218.

It is an arithmetic number, because the mean of its divisors is an integer number (1556415).

Almost surely, 2^65457990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65457990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99610560).

65457990 is an abundant number, since it is smaller than the sum of its proper divisors (133763130).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65457990 is a wasteful number, since it uses less digits than its factorization.

65457990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1143 (or 1137 counting only the distinct ones).

The product of its (nonzero) digits is 340200, while the sum is 45.

The square root of 65457990 is about 8090.6112253649. The cubic root of 65457990 is about 403.0147010299.

It can be divided in two parts, 6545 and 7990, that added together give a triangular number (14535 = T₁₇₀).

The spelling of 65457990 in words is "sixty-five million, four hundred fifty-seven thousand, nine hundred ninety".